MODULE 10

Pharmacology II

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Lifespan Considerations

Pregnant Women If possible, drug therapy should be

delayed until after the first trimester, especially when there is danger of drug-induced developmental defects.

Potential fetal risks must be compared to maternal benefits when drug therapy is required.

Minimum therapeutic dose should be used for as short a time period as possible.

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Lifespan Considerations (cont’d)

Pregnant WomenFDA Pregnancy Categories:

Drugs in categories A and B most likely carry little or no risk to the fetus.

Drugs in categories C and D most likely carry some risk to the fetus.

Drugs in category X are contraindicated during pregnancy.

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Lifespan Considerations (cont’d)

Pregnant Women There are certain situations that

require judicious use of drugs during pregnancy:HypertensionEpilepsyDiabetes Infections that could seriously

endanger the mother and fetus

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Lifespan Considerations (cont’d)

Breast-feeding WomenMany drugs cross from the mother’s

circulation into breast milk and subsequently to the infant, although in small amounts because this is not the primary excretion route.

Again, the risk to benefit ratio must be evaluated.

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Lifespan Considerations (cont’d)

ChildrenParent is important source of:

Information about the childSource of comfort for the childPartner with the health care team

during drug therapy.Should not be used to refer to a

patient under 1 year of age.

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Lifespan Considerations (cont’d)

ChildrenDifferences in Physiology and

PharmacokineticsImmaturity of organs most

responsible Anatomic structures and

physiologic systems and functions are still in the process of developing

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Lifespan Considerations (cont’d)

ChildrenPharmacodynamics (Drug Actions)

Some drugs may be more toxic in children and some less.

More toxic – Phenobarbital, morphine, ASA Same – Atropine, codeine, digoxin Contraindicated – tetracycline (discolor

teeth), corticosteroids (may suppress growth) Fluoroquinolone antibiotics (may damage cartilage leading to gait deformities)

Some tissues may be more sensitive – smaller doses

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Lifespan Considerations (cont’d)

Children - Kid FactsSafe, appropriate drug therapy must

reflect the differences between adults and children.

The child’s stage of growth and development must be considered when assessing core patient variables and the interaction of core drug knowledge and core patient variables.

Pediatric drug dosages must be accurate to reduce risk of adverse effects and prevent over dosage.

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Lifespan Considerations (cont’d)

Children - Drug Administration Choice of appropriate route and/or site

of drug administration will vary by the child’s age and size and the drug.

Special techniques may be needed to minimize traumatic effects to the child:

EMLA cream can be used to numb an area prior to an injection.

A popsicle or ice chips can be used to numb taste buds before unpleasant-tasting oral drugs.

Do not mix drug therapy into infant formula.

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Lifespan Considerations (cont’d)

Children – Nursing ResponsiblitiesEducation about medications should be

provided for the patient, at an appropriate developmental level, and to the family.

Implement the “6 Rights.”It may often be necessary for 2 nurses

to check the medication(s). Check agency policy.

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Lifespan Considerations (cont’d)

Older adults/Geriatric ConsiderationsShare common age-related changes

and risk factors that alter drug administration, dosage and expected response to drug therapy.

All pharmacokinetic processes are altered, placing older adults at higher risk for adverse drug effects.

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Lifespan Considerations (cont’d)

Geriatric Considerations Pharmacokinetics:Alterations in absorption are more likely

caused by disease processes.Distribution is altered because of:

Decreased body mass Reduced levels of plasma albumin Less effective blood-brain barrier

Hepatic metabolism is slowed.Renal efficiency is decreased:

Serum creatinine levels will remain normal even though kidney function is impaired.

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Lifespan Considerations (cont’d)

Geriatric Considerations-Pharmacodynamic Changes Receptor site changes.Blood-brain barrier allows more

drug to enter the brain.Normal aging-related decline in

organ or system function occurs.

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Lifespan Considerations (cont’d)

Geriatric Considerations o Polypharmacy

May see multiple MDs for various illnesses and all may prescribe meds.

Consume approx 32% of all Rx drugs and 40% over the counter (OTC) drugs

Most common Prescriptions – antihypertensives, insulin, beta blockers, digitalis, diuretics, potassium (K) supplements

Most common OTC’s – analgesics, laxatives, nonsteroidal anti-inflammatory drugs (NSAIDS)

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Lifespan Considerations (cont’d)

Geriatric Considerations Nonadherence – Lack of knowledge or

incomplete knowledge leads to misunderstanding about medication regime.

Lifestyle – Choices may have to be made between food, rent and purchase of medications.

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Lifespan Considerations (cont’d)

Geriatric Considerations:Simplify the therapeutic regimen.Give memory aids (if necessary).Give written instructions.Determine financial access to drug

therapies.Assess cultural barriers.Titrate the dose upward slowly to

minimize adverse effects.

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Cultural Considerations in Drug Therapy

The Law of Cultural DiversityEach patient needs to be considered an

individual, regardless of cultural, ethnic or religious beliefs.

Although members of a culture share certain beliefs and practices, individual variation will still occur. Many cultural groups in the U. S. have beliefs that reflect both their original ethnic culture and the dominant culture of the United States.

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Ethnic Considerations in Drug Therapy

Drug polymorphism Critical in understanding a patient’s response

to drug therapy May explain many adverse and idiosyncratic

reactions Refers to how individuals metabolize differently Looks at genetics that often have a common

basis in ethnic background Opens up a new field of study in pharmacology

that has been lacking for years due to societal factors

Examples: Why does the African-American respond differently to antihypertensives, the Chinese patient require lower doses of benzodiazepines, the Caucasian respond differently to some pain medications?

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Ethics and Drug Therapy

Nurse’s responsibility is to always be a patient advocate and remain

nonjudgmental. ANA Code of Ethics Canadian Nurses Association Code of Ethics Various Nurse Practice Acts

All share the framework for the professional practice of nursing.

All believe that, professionally, the nurse provides safe nursing care to patients regardless of the group, community, ethnicity or culture.

Nursing does not impose values or standards on the patient.

Nurses assist the patient and family in facing decisions regarding health care.

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Botanical Dietary Supplements

For a complete list of botanical dietary supplements fact sheets, (National Institutes of Health), see : http://www.ods.od.nih.gov/Health_Information/Botanical_Supplements.aspx

Opioid & Non-Opioid Analgesics

Aspirin

NSAIDs

COX-2 inhibitor

Acetaminophen

Narcotics

The 5th Vital Sign

Pain

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Analgesics

Definition of an analgesic:

“Medications that relieve pain without causing loss of

consciousness”

Pain is a subjective experience. The nurse must believe the patient. PET scans now can visualize brain’s responses to many kinds of pain.

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Proposed Pain PathwayNociceptors (free nerve endings)

Afferent stimulation of sensory “A” or “C”fibers

Dorsal horn spinal cord – the location of the “gate”

3 major brain pathways:Spinothalamic, spinoreticular,

spinomesencephalic

Release of peptide substance P from unmylinated “C” fibers in dorsal horn

(Multiple neurotransmitters released)

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Pathophysiological

Nociceptive pain Neuropathic pain Psychogenic pain

The type of pain determines the analgesic.

Neuropathic pain is often treated with anticonvulsants, tricyclic antidepressants

added onto narcotics

Many theories of pain transmission are not

completely understood.

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Pain Transmission

These techniques also allow some non- pharmacological relief from pain:

Massage Deep pressure

Distraction Relaxation Vibration

Can be used as independent nursing intervention after assessment

The above activate the large “A” fibers.

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Factors Influencing Pain Perception

Type of pain Acute vs. chronic Visceral vs. cutaneous Nociceptive, neuropathic,

psychogenic Intensity of pain & type of injury Inflammatory process Degree of Anxiety

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Factors Influencing Pain Perception

Sensory input Social support Fatigue Age, sex & culture Memory & information processing Level of consciousness Type, amount, route of analgesic

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Drugs Influencing Pain Perception

Narcotics (opioids) modify pain perception via Central Nervous System (CNS) & dorsal horn via binding to Mu, kappa & delta opioid receptors & inhibiting substance “P” and glutamate (an excitorary neurotransmitter).

Alter perception of pain via opiate receptors, and alter psychological responses via brain.

Other mechanisms to alter pain involve effects on the Autonomic Nervous System (ANS), skeletal muscle response & diagnosis.

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Drugs Influencing Pain Perception

Nonopiate analgesics (salicylates, NSAIDS, etc.)

Control pain impulses in the periphery

Often involving the Arachidonic acid pathway responsible for inflammation and an immune response

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Some Pain Mysteries

Phantom pain

Referred pain

Pain experienced after cordectomy

Placebo response

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Prostaglandins

Associated with inflammation Involved in the temperature

set point of the hypothalamus Sensitize pain receptors to

mechanical and chemical stimulation

Found in many cells and body processes

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Leukotrines

Arachidonic acid metabolites

Mediators in inflammation

Synthesized when tissue injury occurs

May be involved in rheumatoid arthritis, asthma and system wide anaphylaxis

Bronchoconstrictor and vasodilator

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Synthesis of Prostaglandins

Arachidonic acid

Lipoxygenase

Cyclooxygenase

Leukotrines Prostaglandins

enzymes

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TWO Enzyme FORMS

CYCLOOXYGENASE-1 & CYLOOXYGENASE- 2

COX-1 COX-2

Prostaglandins

Protects stomach lining

Inflammation Pain

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Peripheral control of pain

Release of prostaglandin inflammation & pain

Prostaglandins mediate pain and swelling by triggering vasodilatation. Prostaglandins are synthesized by the enzyme cyclooxygenase which breaks down arachidonic acid to synthesize prostaglandin. This is the basic method of action of aspirin and NSAIDs.

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Inhibition of Cox-1 & Cox-2

Inhibition of both Cox-1 & Cox-2 will be effective as an:

ANALGESIC ANTIPYRETIC ANTI-INFLAMMATORY AGENT AGENT TO DECREASE PLATLET

AGGREGATION

Also associated with stomach damage due to COX-1 inhibition

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Aspirin

Inhibits both Cox-1 and Cox-2

Is used as a analgesic Is used as a anti-inflammatory agent Is used as a antipyretic But can cause stomach damage Is used to prevent coronary heart

disease (CHD) via platelet aggregation

In what other cases should aspirin NOT be used?

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Aspirin adverse effects & interactions

Tinnitus – sign of toxicity Dyspepsia Highly protein bound so it displaces

other medications: oral anticoagulants, oral hypoglycemics, some anticonvulsives.

G.I. Bleeding increased with glucocorticoids, alcohol

High doses may cause excessive bruising Highly lethal if taken in overdose - No

known antidote Caution with asthmatic patients (may

have aspirin allergy also)

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Hold giving Aspirin

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Children under 15 withviral infection

Reye’s syndrome is associated with aspirin use.

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NSAIDSNon-Steroidal Anti-Inflammatory Drug

First line treatment for inflammation Both COX-1 & COX-2 inhibitors Mild to moderate pain of various types Good for dysmenorrhea Antipyretic Reversibly inhibit platelet

aggregation (less than aspirin because aspirin has irreversible inhibition)

INHIBIT THE PRODUCTION OF PROSTAGLANDINS THAT MEDIATE PAIN AND INFLAMMATION

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Side effects & Interactions of NSAIDs

G.I. Bleeding, dyspepsia Liver toxicity or renal damage with

large doses, prolonged use Highly bound to plasma protein so

displace other medications, leading to exacerbation of their side effects

These adverse effects can occur with oral or parenteral routes and even if

enteric coated.

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Don’t give aspirin or NSAIDs

Patients with ulcers

Patients going to surgery

Patients with an allergy to aspirin

Alcoholic patients

When patient is nauseated or vomiting

Patients on glucocorticoids (without M.D. order)

Patients taking ACEIs (Angiotensin Converting Enzyme Inhibitors)

Caution with NSAIDs in patients with CHF

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COX-2 INHIBITOR

Celecoxib (Celebrex) Approved for osteoarthritis and rheumatoid arthritis

Acute pain & dysmenorrhea Do not give if sulfa allergy

Has anti-inflammatory properties

Only COX-2 inhibitor currently available

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Acetaminophen (Tylenol)

Is a very weak inhibitor of both Cox-1 and Cox-2

Is used as an antipyretic Is used as an analgesic Can not be used as an anti-

inflammatory agent Does not stop platelet aggregation May work by inhibiting

prostaglandin synthesis in the CNS

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Acetaminophen

Is the drug of choice for mild to moderate pain

Is often combined with opioids to treat moderate to severe pain

Will cause liver failure in LARGE doses or prolonged use (2.4 to 4 grams/day)

Liver failure with alcohol due to metabolic pathways

Ceiling effect Overdose is difficult to treat - use

acetylcysteine

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Acetaminophen

Young children, older adults, daily drinkers of 3 or more alcoholic beverages and those with kidney or liver disease are at risk for accidental acetaminophen poisoning

Acetaminophen found in many pharmaceuticals Vicodin ES (5 tabs Q. D. = 4 gm) Tylenol extra-strength (8 tabs = 4 gm) What other OTC medications might

contain acetaminophen?

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Neuropathic Pain

Difficult to treat Use of opioids does not completely control

pain Usually add on another medication from a

different class (co-analgesic agents) immipramine (Tofranil) Tricyclic

antidepressant -TCA gabapentin (Neurontin) Anticonvulsant Duloxetine (Cymbalta) newest SNRI

(serotonin norephinephrine reuptake inhibitor) - also used for depression

Effexor is another medication in this class

New pregabalin (Lyrica) anticonvulsant - alpha2 - delta ligand

+ other medication classes

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Natural, synthetic and semisynthetic

ALL COMPARED TO MORPHINE

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Opiates

Narcotics: Very strong pain relievers

Opiates: Pain relievers that contain

opium, derived from opium, or are chemically related to opium

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Pain Transmission

o Body has endogenous neurotransmitters

o Endogenous neurotransmitters are: enkephalins & endorphins (morphine-like peptides) produced by body to fight pain

o Opiates bind to these natural endogenous opioid receptors

o Inhibit substance P in dorsal horn of spinal cord

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Chemical Classification of Opioids

CHEMICAL CATEGORY & examplesNatural: codeine, morphine

Semi-synthetic: hydrocodone (Vicodin) oxycodone + salicylate

Synthetic: meperdine (Demerol) can beneurotoxic and cause

confusion/seizure - NEVER give to patients with

Parkinson’s Diseasebutalbital (Fiorinal)

(Percodan)

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Opiates

Three classifications based on their actions:

agonist agonist-antagonist partial agonist

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CNS Opiate effects/uses

Analgesia Cough suppression Euphoria Reduces fear/anxiety Raises pain threshold (decreased

awareness) Sleep induction Respiratory depression Pupil constriction (miosis) Nausea and vomiting

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Peripheral Nervous System OPIATE Effects

Constipation Urinary retention Diaphoresis & flushing Hypotension due to

vasodilatation

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Narcotic analgesic routes

PCA example Morphine (acute pain) Transdermal example Duragesic patch

(fentanyl) (chronic pain) Epidural example fentanyl or morphine Oral example MS Contin (morphine)(chronic

pain) I.M injections example meperidine (acute

pain) (Demerol). Do not give for more than a day – neurotoxic, lowers seizure threshold, not first line agent. Metabolite normeperidine neurotoxic and may cause psychosis in the elderly patient.

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Gold Standard is Morphine No ceiling effect

ADVANTAGES Decreased

awareness Decreased anxiety Increased sleep Decreased pain

perception

DISADVANTAGES Hypotension Constipation Nausea Respiratory

depression Itching

Secondary effects of cough suppression and constipation are used therapeutically

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Oral Morphine examples

Oxycontin (oxycodone) MS Contin (morphine) Kadian (morphine) Oramorph SR (morphine) Avinza (morphine)

New Q day dosing (Do not crush, chew or dissolve the caps or could deliver fatal dose)

If can not swallow, O.K. to open & sprinkle the beads on applesauce

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Mixed agonist-antagonists

Pentazocine (Talwin)Buprenorphine (Bupreneax)Butorphanol (Stadol)Ultram (Tramadol) - mechanism of action

not clearly understood, weak bond to opioid receptors & inhibits reuptake of norepinephrine (NE) & serotonin (5-HT) may cause chemical dependency

These medications are rarely used

DO NOT GIVE THESE MEDICATIONS TO PATIENTS WHO ARE DEPENDENT ON

NARCOTICS.

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Opiate Antagonists/blockers

Naloxone (narcan) opiate antagonist [competitive]

Naltrexone (ReVia) now used to help alcoholics stay abstinent

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Opiates

Opioid Tolerance:

a common physiologic result of chronic opioid treatment

means larger doses of opioids are required to maintain the same

level of analgesia

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Opiates

Physical Dependence The physiologic adaptation of the

body to the presence of an opioid

Opioid tolerance and physical dependence are expected with long-term opioid treatment and should not be confused with psychological dependence [addiction].

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Opiates

Psychological Dependence[addiction]

A pattern of compulsive drug use characterized by a continued craving for an opioid and the need to use the opioid for effects other than pain relief

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Opiates

Misunderstanding these terms leads to ineffective pain management and contributes to the problem of under treatment.

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Opiates

Physical dependence on opioids is known when the opioid is abruptly discontinued or when a opioid antagonist is administered. narcotic withdrawal opioid abstinence syndrome

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Opiates

Narcotic withdrawal Opioid abstinence syndrome

Manifested as: (flu-like symptoms)Anxiety, irritability, chills and hot flashes, joint pain, lacrimation, rhinorrhea, diaphoresis, nausea, vomiting, abdominal cramps and diarrhea

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Drugs Affecting the Autonomic Nervous System

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Photo Source: National Institutes of Health, Public Domain, http://catalog.niddk.nih.gov/ImageLibrary/searchresults.cfm

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Sympathetic NS

FIGHT FLIGHT&

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Parasympathetic N.S.

BREED & FEED

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Adrenergic Drugs

Mechanism of action Mimic Sympathetic Nervous System (N.S.) Have sympathomimetic properties Have sympatholytic action also since they

oppose the parasympathic N.S. Catecholimines are neurotransmitters

involved in adrenergic system DA (dopamine) NE (norepinephrine) E

(epinephrine) Energizing neurotransmitters

Direct-acting, indirect acting and mixed adrenergics

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Adrenergic Drugs (cont’d)

Indications Bronchodilation (albuterol) Cardiac stimulation, alpha1, beta 1,

beta 2, increase blood pressure (dopamine, isoproterenol)

Mental alertness & wakefulness (monafnil)

Appetite suppression (adipex) Decongestion (pseudoephedrine) Open angle glaucoma (dipivefrin)

produces mydriasis = pupil dilation ADHD (methylphenidate)

Adverse effects Tachycardia, hypertension, anxiety,

insomnia, psychological dependency

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Alpha -Adrenergic Blocking Drugs

Drug examples: ergotamine tartrate (Egostat), Phenoxybenzamine, phentolamine (Regitine)

Indications: Raynaud’s disase, hypertension secondary to pheochromocytoma, extravasation of vasopressors, vascular headaches

Adverse effects: nasal congestion, orthostatic hypotension, tachycardia, dizziness, (Gastrointestinal) GI irritation, and miosis. Ergotamine may cause chronic poisoning.

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Beta-Adrenergic Blocking Drugs

Drug examples: selective for beta 1 receptors - atenolol, metoprolol Non-selective for beta 1 & 2 receptors - propranolol (contraindicated in pt. with COPD, asthma, depression)

Indications: treat hypertension, angina, tachyarrhythmias, CHF, Post MI because they are cardio-cardio-protective

Contraindications: bradyarrhythmias, bronchospasm, heart blocks

Adverse effects: arrhythmias, bradycardia, bronchospasm, nausea, vomiting, diarrhea, increased sensitivity to cold, rebound HTN if stopped abruptly

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Cholinergic Drugs

cholinergics cholinergic agonists

parasympathomimetics Sympatholytics

All are terms that refer to drugs that stimulate the Parasympathic Nervous

System

MIMIC ACETYLCHOLINE Cholinergic drugs

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Cholinergic Drugs

Cholinergic receptors [two types]

Based on location & their action

Nicotinic {N}&

Muscarinic {M}

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Drug & Side Effects of Cholinergics

SalivationLacrimationUrinary incontinenceDiarrheaGastrointestinal crampsEmesis

(Also bronchospasm, decreased intra ocular pressure (IOP), decreased heart rate, increased bronchial secretions, miotic, sweating)

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Cholinergic Drugs Indications Direct- acting

Cholinergic agonists – used to treat open angle glaucoma and dry eyes and to stimulate bladder

Indirect-acting Cholinesterase inhibitors (reversible) – for

Alzheimer’s & to treat myasthenia gravis (MG) and open angle glaucoma not responsive to other agents – prevents postoperative paralytic ileus

Drug examples – bethanechol, pilocarpine Bethanechol – treat nonobstructive urine retention,

neurogenic bladder, adynamic ileus Pilocarpine – treat glaucoma

Contraindications Possible urinary or GI obstruction and pregnancy

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Cholinergic-blocking drugs

Class of drugs that block or inhibit the actions of Acetylcholine in the Parasympathetic Nervous System

anticholinergics parasympatholytics

antimuscarinic agents

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Cholinergic-blocking drugs (also called anti-cholinergic drugs)

Inhibit nicotinic {N} or muscarinic {M} receptors

Anticholinergic effects are the result of muscarinic blockage, primarily on the post synaptic receptor of the Parasympathetic Nervous System.

There are medications that are designed for their anticholinergic effect.

Many medications have anticholinergic side effects that are NOT wanted.

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Cholinergic-blocking drugs

Atropine Preop for secretion control, therapeutic

anticholinergic effect, Bradycardia, anticholinesterase effect for insecticide poisioning CNS excitation

Dicyclomine (Bentyl) Irritable bowel syndrome (IBS)

Propantheline bromide (Pro-Banthine) Adjunct in Treatment of peptic ulcer, IBS,

pancreatitis

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Cholinergic-blocking drugs

Glycopyrrolate (Robinul) Control of secretions intraoperative,

preop control of secretions, preop for electro convulsive therapy (ECT)

Scopolamine (Transderm-Scop) Prevents motion sickness

Orphendrine (Norflex) A central acting anticholinergic muscle

relaxant

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Therapeutic effects of Anticholinergics

Tolterodine (Detrol) & Trospium Chloride (Sanctura) newOveractive bladder

Benztropine (Cogentin)Parkinson’s DZ and EPS (neurological

side effects) from antipsychotics

Ipratropium Bromide (Atrovent)Inhaled drug used to treat COPD,

asthma, little systemic effect because inhaled

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Drug Interactions

ADDITIVE EFFECTS WITH: antihistamines, anticholinergics, phenothiazines,tricyclic antidepressants, MAOI’s (monoamine oxidase inhibitor)

Antihistamines have anticholinergic effects

This could cause confusion & or psychosis in the ELDERLY PATIENT.

Contraindicated in: glaucoma, benign prostatic hypertrophy (BPH), Cardiac disease and obstructive bowl & asthma unless inhaled

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Secondary effects/Side effects

(anticholinergic)

Xerotomia (dry mouth) Blurred vision Urinary retention Decreased perspiration Constipation Tachycardia

These are common in many of the psychoactive drugs

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Neuromuscular Blocking Agents

Prevent nerve transmission in certain muscles, leading to paralysis of the muscle at neuromuscular junction by binding to Ach receptor

Indications – Maintains controlled ventilation during mechanical ventilation or during endotracheal intubation

Contraindications – Drug allergy, previous history of malignant hypertension, penetrating eye injuries and narrow-angle glaucoma

Side/Adverse Effects – Hypokalemia, dysrhythmias, fasciculations, muscle pain, increased intraocular and intracranial pressure and apnea

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CNS Depressants Hypnotics and Sedatives

Classified into barbiturates, benzodiazepines and miscellaneous agents

Act primarily on the brainstem; sedative and hypnotic effects are dose related.

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Barbiturates

Habit forming and have narrow therapeutic index

Contraindications –pregnancy, significant respiratory difficulties and severe liver disease

Side Effects – Drowsiness, lethargy, dizziness, hangover, and paradoxical restlessness or excitement

Adverse Effects – Vasodilatation, hypotension blood dyscrasias, hypersensitivity reactions

Interactions – synergistic with other Central Nervous System (CNS) depressants

Can be lethal in overdose Can have lethal consequences of

uncontrolled withdrawal

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Short-term treatment of insomnia (rare) Sedation in lower doses Ultra-short acting for anesthesia

induction Pre-op medication Epilepsy, mainly status, but the long-

acting Phenobarbital can be used as anticonvulsant - at small doses does not produce sedation, but seizure activity

Not used as often today because of newer agents for sleep, seizure and anxiety

Barbiturates Uses

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Action and General Characteristics of Benzodiazepines

Specific for cerebral cortex and limbic system

Also called anxiolytics Increase action of GABA + other

inhibitory neurotransmitters Highly lipid soluble to facilitate

crossing into CNS Highly bound to plasma protein Metabolized by the liver, some with

long duration of action due to active metabolites

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Benzodiazepine Uses Anxiolytics – examples: alprazolam (Xanax) Anticonvulsants – examples: clonazepam

(Klonopin) and diazepam (Valium) Anesthesia induction – examples:

midazolam (Versed), diazepam (Valium) Muscle Relaxant – example: diazepam

(Valium) Withdrawal from alcohol – example:

chlordiazepoxide (Librium), diazepam (Valium)

Hypnotics – examples: flurazepam (Dalmane), and temazepam (Restoril) do not depress REM sleep; but prevent deep sleep (not natural)

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Secondary/side effects of Benzodiazipines

Daytime sedation Ataxia Dizziness Anterograde amnesia Idiosyncratic paradoxical excitement SELDOM FATAL IF TAKEN ALONE Can be dangerous for the elderly

because of fall potential

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Centrally Acting Muscle Relaxants

Primarily used for the relief of painful musculoskeletal conditions–muscle spasms and spasticity.

Side Effects – Euphoria, lightheadedness, dizziness, drowsiness, fatigue and muscle weakness - usually short-lived

Adverse Effects – GI upset, headache, slurred speech, constipation, sexual difficulties in men, hypotension, tachycardia and weight gain

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Anticonvulsant Medication

Congenital abnormalities Metabolic disorders – hypocalcemia Trauma – accidents Tumors – brain plus status post

craniotomy Vascular diseases – stroke Degenerative disorders- Alzheimer’s Infectious diseases – meningitis, AIDS Fever & toxins Medications – example = antipsychotics Alcohol withdrawal + hypomagnesemia

Causes of SeizureCauses of Seizure

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Types of Seizureaccording to International League Against Epilepsy

Partial Seizures: focal area of brain initiates seizure

Simple partial: focal symptoms, aura, conscious

Complex partial: simple then impairment in consciousness

Generalized partial: spread to both hemispheres

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Types of Seizure

Generalized Seizures: both hemispheres usually effected, unconscious

Absence seizures: impairment of consciousness, autonomic components, usually in children/adolescence

Tonic-clonic: (grand mal) tonic is muscle stiffing, clonic is jerking

Monoclonic: single or multiple jerks

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Status Epilepticus

Single seizure lasting for 20 minutes or longer

Or recurrent generalized seizures without regaining of consciousness in between each seizure episode

Considered a medical emergency

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Possible Action of Anticonvulsants

Pharmacologically distinct action for each group of anticonvulsants is PROPOSED

Many mediate actions by limiting discharge from a focal point – surrounding it

Others elevate seizure threshold through neurotransmitters or ions

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Possible General Mode of Action

Increase concentrationIncrease concentration

of GABA byof GABA by

Blocking reuptake into glia & nerve endings

Inhibiting enzymes that catabolize GABA

Facilitating GABA & other inhibitory receptors

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Mode of Action other than potentiation of GABA

Suppression of calcium influxInhibition of voltage-sensitive sodium channelsBinding to the amino acid glycine (neurotransmitter & inhibitory A.A.) at receptor siteDecreasing metabolism of glutamate

EXACT MODE OF ACTION NOT KNOWN

Agent chosen depends on type of seizure, age, sex, pharmacologic properties, side effects and cost

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Anticonvulsants

FIRST LINE AGENTS - USED AS MONOTHERAPY for Tonic Clonic Seizures

Phenytoin ( Dilantin) Carbamazepine (Tegretol) Valproic acid (Depakene or

Depakote) Primidone (Mysoline) Phenobarbital

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Anticonvulsants

FIRST LINE AGENTS USED AS FIRST LINE AGENTS USED AS MONOTHERAPY forMONOTHERAPY for Partial Partial SeizureSeizure

Carbamazepine (Tegretol) Valproic Acid (Depakene or Depakote) Lamotrigine (Lamictal) Topiramate (Topamax)* Gabapentin (Neurontin)*

* Not FDA approved for monotherapy, but studies support

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Anti-convulsant Drugs(Antiepilieptics)

Indications: Prevention and control of seizures Main adverse effects of most anticonvulsants

are mental confusion and drowsiness Interactions of many older meds:

Potentiate CNS depressants and alcohol Concurrent use with tricyclic antidepressants or

phenothaizines lowers the seizure threshold and decreases the effectiveness of anticonvulsants

Many drugs alter hepatic metabolism of anticonvulsants leading to decreased serum levels and loss of seizure control and toxicity

Phenytoin’s cytochrome P-450 enymatic reaction inhibits atazanavir’s action (depakote becomes the drug of choice in this example).

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Anti-convulsant Drugs Hydantoins Drug examples: Mephenytoin, phenytoin

(Dilantin) Indications: treat tonic-clonic (grand

mal) seizures and complex partial seizures, arrhythmias, and painful condition such as trigeminal neuralgia

Adverse effects: (long term) gingival hyperplasia, liver function abnormalities, blood dyscrasias, (toxicity) as evidenced by diplopia, nystagmus, ataxia, and drowsiness

Caution driving or operating equipment because of mental confusion

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Anti-convulsant Drugs

Tell patient to use alternate birth control if on the pill

Supplement with Vitamin D, Calcium and folic acid

Interactions with Calcium Channel Blockers, Antipsychotics and steroids

P-450 = many interactions

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Anti-convulsant Drugs

Interactions…Oral tube feedings with osmolite or

isocal may interfere with absorption of oral dilantin diminishing drug’s effectiveness

IV dilantin precipitates with D5W. Characteristics of fosphenytoin

(Cerebyx) – preferred over IV Dilantin Prodrug of phenytoin Rapidly converted by blood and liver

enzymes to phenytoin (Dilantin) Given I.V. only

108

Anti-convulsant Drugs

Barbiturates and deoxybarbiturates Examples: Mephobarbital, phenobarbital,

primidone Indications:

Treat tonic-clonic seizures, partial seizures and insomnia

Used as adjuncts to anesthesia Adverse effects: Dizziness, drowsiness,

hypotension, respiratory depression with high doses

Interactions: Drugs decreases serum dilantin level when used concurrently

Primidone plus phenobarbital may cause phenobarbital toxicity

109

Anti-convulsant Drugs

Benzodiazepines Examples: clonazepam (Klonopin)

Diazepam (Valium)

Indications: treat absence seizures, status epilepticus, anxiety and skeletal muscle spasms.

Adverse effects: ataxia, drug dependence, respiratory and cardiovascular depression

110

Valproic acid (Depakene) Divalproex (Depakote)

Low side effect profile, well tolerated May cause liver failure (rare) in first

6 months of therapy Lethargy, muscle weakness, sedation Leukopenia Ataxia Depakene causes nausea/vomiting Interacts with many other

anticonvulsants

111

Nursing Considerations

Good for generalized and partial seizure

Monitor blood levels Monitor CBC and liver function tests Highly protein bound, do not take

with NSAIDs, aspirin & other drugs that alter coagulation

Potentiates CNS depressants Reassure patient of alopecia, hair

will re-grow Used as mood stabilizer for bipolar

disorder and has FDA approval for this

112

Carbamazepine (Tegretol)

Blood dyscrasias * Notify health care provider

Liver toxicity Rash Drowsiness Low side effect profile – well

tolerated

* Immediately discontinue & switch to another agent

113

Nursing Considerations

Low behavioral and toxicologic profile Good for both generalized and partial

seizures Autoinduction – dosage needs

monitoring via blood levels, decreases after initial doses

Advise alternate birth control if on pill Monitor CBC for bone marrow

depression Used “off label” as mood stabilizer for

bipolar disorder

114

Lamotrigine (Lamictal)

Monotherapy in partial seizures Well tolerated No weight gain, no sedation Rare, but can be associated with

life threatening rash (Stevens-Johnson syndrome)

Nausea, vomiting, weight loss (rare)

Dizziness, ataxia

115

Nursing Considerations

Discontinue at once if rash/inform health care provider

Nurse asks patient every visit Taper on very slowly to avoid rash – 25 mg

Q 2 weeks until 200 mg No blood levels required Note many anticonvulsants raise or lower

plasma levels Monitor for adverse reactions if not

monotherapy May reduce effectiveness of estrogen Used for mood disorder in bipolar, good for

depressive side, and has FDA approval for this

116

Topiramate (Topamax)

Adjunctive therapy in partial and generalized seizures (studies support monotherapy)

Well tolerated Fatigue Confusion Difficulty concentrating, speech

problems (unable to recall words) Nausea Weight loss No blood levels required

117

Gabapentin (Neurontin)

Adjunct therapy for partial seizures (studies demonstrate monotherapy)

Excellent side effect profile Main problem is initial sedation, ataxia Not metabolized by liver so no interactions

with other anticonvulsants Used extensively for neurogenic pain Excellent for elderly and those on poly

drugs No blood levels required Used “off label” as mood stabilizer for

bipolar disorder but no FDA approval for this

118

Other uses for Anticonvulsants

Mood stabilizers Migraine headache Neurological pain Chronic pain syndrome Anxiolytics

119

Anti-Parkinsonian Drugs Groups of Drugs Used

Antidyskinetic Drugs or anticholinergics Antihistamines (have anticholinergic

effects) Dopaminergics

Dopaminergic agonistsMAOI-B (monoamine oxidase inhibitor)COMT Inhibitors (catechol-0-methyl-transferase)

120

Anti-Parkinsonian Drugs

Dopaminergic agonists are mainstayContraindications and precautions:

Used with caution in patients with residual arrhythmias after MI, history of peptic ulcer, psychosis or seizure disorders

Contraindicated with narrow angle glaucoma Used with caution for patients with bronchial

asthma, emphysema, or severe cardiovascular, pulmonary, renal, hepatic or endocrine disease

Adverse Effects: Dizziness, confusion, mood changes,

orthostatic hypotension, nausea, vomiting, hallucinations

121

Anti-Parkinsonian Drugs

General Information Mechanism of of action: Restore the natural

balance of the neurotransmitters in CNS to decrease S/S of Parkinson’s Disease. Imbalance between Achetylcholine (ACH) and Dopamine. Too much ACH and too little dopamine. Meds correct this.

Dopaminergic agonists Mechanism of Action is to increase the amount of

DA available in the CNS or enhance the neurotransmission of Dopamine

Medication examples: Levodopa restores dopamine levels Amantadine increases the amount of dopamine in

the brain Pramipexole (Mirapex) – newer DA receptor agonist Ropinirole (Requip) – newer DA receptor agonist

122

Anti-Parkinsonian Drugsanticholinergics

Drug examples: Benztropine (Cogentin) Trihexyphenidyl (Artane) Procyclidine (Kemadrin)

Indications: Bradyarrhythmias, dyskinesia, parkinsonism, peptic ulcer

and bowel spasms Nausea, vomiting, induce mydriasis, decrease salivation

and bronchial secretions before surgery Contraindications:

Narrow-angle glaucoma, severe hemorrhage, uncontrolled tachycardia, urinary tract/GI obstruction, BPH

Adverse effects: Blurred vision, conjunctivitis, and photophobia,

tachycardia, constipation, dry mouth and urinary hesitancy

CAN CAUSE PSYCHOTIC CONFUSION IN THE ELDERLY when drugs with anticholinergic effects are combined.

123

Two Newer class to treat Parkinsons

Selegiline (Eldepryl)

MAOIB (monoamine oxidase inhibitor – B) May have neuroprotective effects slowing the

progression of the Disease Tolcapone (Tasmar) & entacapone (Comtan)

Catechol O-methyltransferase (COMT) inhibitors = newest class

Not used as monotherapy, but as add on to levadopa to increase its efficacy.

Tasmar has been associated with liver dysfunction.

124

Two classes that reduce dosage of Levadopa

MAOI-B DA in brain by inhibiting its metabolism by MAO. Form “B” metabolizes DA. At oral doses < 10mg Q.D. like MAOI- A so acts more on tyramine NE, E, DA & 5H-T. No food restrictions with low doses.

COMT inhibitors work by inhibiting the enzyme catechol-O-methyltransferase the 2nd enzyme involved in the metabolism of levodopa - so increased amount of levodopa available.

125

Wearing off syndrome

Doses need to be adjusted upward and downward as adverse mental changes occur or Parkinson’s symptoms worsen.

Changing doses is done slowly.

126

Advanced Parkinson’s

A new DA agonist Apomorphine (Apokyn) given S.Q. is available for advanced Parkinson’s as a rescue drug for acute rigidity.

This is temporary add on, not replacement. N/V. Rx for antiemetic.

Not 5-HT3 antagonists like ondansetron (Zofran) because of hypotension.

Use trimethobenzamide (Tigan). Why do you NOT want to use prochlorperazine (Compazine)??

127

Drugs used to Treat Alzheimer’s

Cholinesterase inhibitors Increase Acetylcholine (Ach) in key

areas of brain (cerebral cortex) Reversible cholinesterase inhibitors Used to Treat mild to moderate disease Do not reverse symptoms; slow

progression Check P450 for drug interactionsExamples Donepezil (Aricept) Tacrine (Cognex) (1st, most adverse

effects, not used today) Rivastigmine (Exelon) – newer {may

have greater efficiacy}

128

New class to Treat Alzheimer’s

Memantine (Nameda) Released Jan. 2004 for

Treatment of moderate to severe Alzheimer’s Disease

May have more favorable side effect profile than Ach inhibitors

May be possible to combine with ACh inhibitors for better result

129

Drugs Affecting the Cardiovascular and Renal

Systems

Drugs to Treat:

Congestive heart failure

Hypertension

Angina

130

Inotropic (increase force of contraction)

Drugs and Cardiac Glycosides Indications

Used to treat CHF in combination with other medications.

Control ventricular rate in atrial fibrillation, atrial flutter, paroxysmal atrial tachycardia

Contraindications and precautions Uncontrolled ventricular arrhythmias, constrictive

pericarditis, complete heart block Increased risk of toxicity with hypercalcemia,

hypokalemia, hypomagnesemia, hypothyroidism, or renal failure

Very narrow therapeutic index Elderly patients more sensitive to toxic drug

effects Adverse effects – bradycardia, fatigue, weakness,

nausea, vomiting, diarrhea, visual disturbances Monitor pulse – hold if less than 60/min. apical Do not increase longevity in CHF

131

Inotropic Drugs and Cardiac Glycosides

Interactions K-wasting diuretics and other drugs causing K loss

increase risk of toxicity Amiodarone, diflunisal, diltiazem, nifedipine,

quinidine, verapamil increase the serum drug level and may cause toxicity

Concurrent use of beta adrenergic blocking drugs causes additive bradycardia

Antacids, cholestyramine, and colestipol decrease the absorption of cardiac glycosides

Digitalis preparations Examples: Digitoxin (long ½ life –not used often),

digoxin Nursing responsibilities

Digoxin excreted unchanged by the kidneys, dosage must be reduce with renal impairment

Monitor serum digoxin levels to prevent toxicity Digoxin Immune Fab IV to reverse toxicity

132

Antihypertensive Drugs

Antihypertensive drugs Indications

HTN not controlled by life style modifications Classes

Beta-adrenergic blocking drugs, angiotensin-converting enzymes (ACE) Inhibitors, angiotensin-receptor blockers,(ARB’s), calcium channel blockers, alpha 1 blockers, centrally acting alpha 2 agonists, diuretics, peripheral acting vasodilators

Contraindications and precautions Each class has own action, side effects,

specific recommendations and adverse reactions

133

Antihypertensive Drugs2nd line agent

Peripheral vasodilating drugs Drug examples: hydralazine Mechanism of action: exert direct

action on both arteries and veins to decrease peripheral vascular resistance (with beta blockers)

Indications: treatment for hypertension and hypertensive crisis

Adverse effects: fluid retention, tachycardia, orthostatic hypotension, severe hypotension and nausea

Nursing responsibilities Closely monitor for fluid volume excess Rarely used

134

Antihypertensive Drugs ACE Inhibitors (1st line agent)

Drug examples: benazepril, catopril, enalapril, fosinopril, lisinopril

Mechanism of action: block conversion of angiotensin I to angiotensin II

Mode of Action Vasodilation due to inhibition of Renin Angiotension

Aldosterone system, decreased blood volume due to decreased (Sodium) Na+

Adverse effects: dizziness, light-headedness, fainting, tachycardia, palpitations, rash, proteinuria

Nursing responsibilities Not effective with African Americans Do not give with Na+ sparing diuretics Monitor for dry cough Contraindicated in pregnancy and renal stenosis Not to be given with lithium and caution with NSAIDs

Indications: HTN, CHF, diabetes, Angina

135

Antihypertensive Drugs Calcium channel blockers (1st line

agent) Drug examples:

Amlodipine, diltiazem, felodipine, verapamil, nifedipine Mechanism of action:

Dilate vessels by blocking the slow channel, preventing calcium from entering the cell

Adverse effects: Grapefruit juice can cause toxic overdose Dizziness, AV blocks, headache, edema, flushing,

nausea, constipation, bradycardia P-450 interaction with other meds Do not give with grapefruit juice- can cause toxic

overdose Nursing responsibilities

Watch for weight gain if CHF Indications: Angina, arrhythmias, HTN

136

Antihypertensive Drugs

Diuretics – thiazide (1st line agent) Drug examples: chlorothiazide,

hydrochlorothiazide Mechanism of action: inhibit sodium and

chloride reabsorption, distal tubule, reduce blood volume

Adverse effects: Fatigue, dizziness, orthostatic hypotension, rash,

hypokalemia, hyperglycemia Indications: 1st line for HTN, take in the morning

Diuretics – loop Mechanism of action: Loop of Henley, reduce

blood volume example: furosemide (Lasix) Adverse effects: electrolytes Indications: CHF

137

Antihypertensive Drugs

Selective Beta Blockers – 1st line agent

Drug examples: Atenolol Mechanism of action: Selectively block beta 1

receptors in the heart so slows heart rate – chronotropic effect and – inotropic effect

Adverse effects: Bradycardia, rebound HTN if abruptly stopped, fatigue, dizziness, dyspnea

Indications: HTN, Prophylaxis for angina, CHF, post M.I. for cardioprotective effects

Nursing responsibilities: Monitor pulse, watch for drug interactions (CCBs), potentiated by alcohol and other CNS depressants, give cautiously with asthma patients

138

Antihypertensive Drugs

Angiotensin-receptor blockers Alpha 1 blockers Centrally acting alpha 2

agonists

All 2nd line agents

139

Antianginal Drugs Mechanism of action:

Reduce myocardial oxygen demand or increase coronary blood supply

Indication: Angina pectoris

Contraindications: Hypotension, uncorrected hypovolemia

Adverse effects: Flushing, headache, orthostatic hypotension

Interactions: Produce additive hypotension when used with

alcohol, antihypertensives, beta-adrenergic blocking drugs or calcium channel blocker drugs for erectile dysfunction.

140

Antianginal Drugs Nitrates

Drug examples: Erythrityl tetranitrate, isosorbide dinitrate

(Isordil) Nitroglycerin, Nitro-BIDMechanism of action:

Produce vasodilation. Decrease preload and afterload, and reduce myocardial oxygen consumption

Indications: Management of angina, and chronic

anginal attacks Beta Blockers and Calcium Channel

Blockers also for long term management

141

Diuretic Drugs Thiazide and thiazide like diuretics

Drug examples: Clorothiazide, hydrochlorothiazide

Mechanism of action: Increase sodium and water excretion by inhibiting sodium reabsorption in the distal tubule of the kidney

Contraindications: Sensitivity to sulfonamides Adverse effects: Hypokalemia, hyperglycemia,

arrhythmias, orthostatic hypotension, weakness, muscle cramps, photosensitivity reactions

Interactions: Decrease excretion of lithium causing toxicity Concurrent use with other K-depleting drugs and

cardiac glycosides may cause low K and risk of digitalis toxicity

NSAID may reduce response to thiazide diuretics Do not take if allergic to sulfa drugs

142

Diuretic Drugs

Loop diureticsDrug examples:

Bumetanide (bumex) ethacrynic acid, lasix, torsemide

Mechanism of action: Inhibit sodium and chloride reabsorption

from the loop of Henle and the distal tubuleAdverse effects:

Metabolic alkalosis, hypovolemia, dehydration. Hyponatremia, hypokalemia, hypochloremia, hypomagnesemia, photosensitivity, orthostatic hypotension

143

Diuretic Drugs K-sparing diuretics

Drug examples: Amiloride, spironolactone, triamterene

Mechanism of action: Act at the distal tubule to cause excretion of

sodium, bicarbonate, and calcium and conservation of K

Adverse effects: Hyperkalemia, nausea, vomiting, diarrhea

Interactions: Decrease excretion of lithium Concurrent use with ACE inhibitors or K

increases risk of hyperkalemia NSAIDs may reduce the effects of K sparing

diuretics. Give cautiously with renal insufficiency patients

144

Diuretic Drugs Osmotic diuretics

Drug examples: Mannitol, Urea

Mechanism of action: Increase osmotic pressure of the

glomerular filtrate inhibiting reabsorption of water and electrolytes

Osmotic diuretics create an osmotic gradient in the glomerular filtrate and the blood

Adverse Effects: Hyponatremia, dehydration, circulatory

overload, rebound IICP

Antilipemics

DRUGS TO LOWER CHOLESTEROL:VDRL, LDL and TGs

WE EAT TOO MUCH FAT

in the typical American diet.

146

Syndrome Xmetabolic syndrome

Glucose intolerance

Insulin resistance

Hypertension

Dyslipidemia

Hypertriglyceridemia

Male-shaped obesity

Female hip-to-waist ratio

Associated with

Cardiac Disease

147

Classes that lower lipids

HMG-CoA Reductase Inhibitors or Statins

Nicotinic Acid Fibric Acid Derivatives Cholesterol Absorption

Inhibitors

•Bile Acid Sequestrants

148

Anticoagulant, antiplatelet and thrombolytic drugs

Anticoagulant drugs prevent extension and formation of clots by inhibiting factors in the clotting cascade

Thrombolytic drugs activate plasminogen, leading to its conversion to plasmin

Antiplatelet drugs interfere with platelet aggregation, preventing thromboembolic events

149

Common Pathway

Prothrombin

(factor II)

Thrombin

Fibrinogen

Fibrin clot

Factor X

Heparin + antithrombin =

Activated Heparin

Low molecular weight heparin

Vit. K + warfarin

Clot dissolves

plasminogenplasmin

Thrombolytics

Photo Source: Used courtesy of E. McCabe, RN, Santa Barbara City College

150

Anticoagulants Examples: Dalteparin, enoxaparin, heparin,

warfarin Indications: prevent and treat thromboembolic

disorders such as DVT, PE, and atrial fibrillation with embolization

Adverse effects: thrombocytopenia (with heparin) Androgens, chloral hydrate, chloramphenical,

metronidazone, quinidine, sulfonamides, thrombolytic drugs, and valproic acid increase the risk of bleeding and enhance the effects of coumadin

Alcohol, barbiturates, estrogen-containing oral contraceptives and foods high in Vitamin K increase risk of clotting and may decrease effect of heparin

151

Heparin

Accidentally discovered by medical student in 1916, used medically first time in 1935 on humans

High molecular weight – called unfractionated

Does not cross the blood brain barrier – can be used during pregnancy

Half life IV = 45 to 90 minutes Half life SQ = 60 to 120 minutes Bioavailabity is about 20 to 30 %

152

Heparin

Destroyed by enzymes in the GI tract

Administered IV or SQ – IM = muscular hematomas

Varying bioavailability Monitor with - aPTT (activated

partial thromboplastin time) = Preferred because more

sensitive to intrinsic pathway

153

Heparin

Most serious side effect is hemorrhage Administer protamine sulfate by slow IV infusion

to neutralize heparin Drug-drug interactions: antiplatelet drugs,

NSAIDs oral anticoagulants, nitroglycerin, cephalosporins, penicillins, salicylates all may affect of heparin

Uses: Hemodialysis, open-heart surgery, prevention of thromboembolism, post MI, inhibits platelets from binding, DVT, PE, atrial fib, stroke prevention a.k.a. acute brain attack or CVA

Highly protein bound = variable anticoagulation b/c the ill have reactive proteins that also bind to heparin.

154

Anticoagulants

Nursing Responsibilities Heparin given initially because of its

rapid action, then switch to coumadin over several days until therapeutic level is reached

Heparin affects PTT and coumadin PT Inject SQ in abdomen and do not

aspirate or rub at injection site Protamine sulfate antidote for heparin Vitamin K antidote for coumadin Soft toothbrush and electric razor

155

Anticoagulants Monitoring heparin therapy

Obtain baseline PTT Administer a bolus dose of heparin IV,

as ordered Follow with continuous infusion as

ordered Obtain follow up PTT at specified

Values> 1 ½ time the controlContinue to monitorAssess for S/S of bleeding

Values < 1 ½ time the controlContact MDAnticipate dosage increase Increase dosage as ordered

156

Low molecular wt. Heparinexample enoxaparin (Lovenox)

Given by SQ injection Mainly Acts on factor X to begin

the coagulation cascade to inhibit the conversion of prothrombin to thrombin. Produces greater prothrombin effect than binding to factor II as Heparin does.

Also called fractionated heparin

157

Low Molecular wt. Heparin

T.I.A.s Ischemic symptoms Unstable angina Atherosclerosis Non ST elevation M.I. a.k.a, Q wave

M.I. (without elevated enzymes - homocystine)

ST elevations a.k.a. acute M.I. (with elevated enzymes- homocystine)

158

Low molecular wt. Heparin

High bioavailability and so more predictable than heparin because binds to factor X

No routine testing required Can be administered at home Bleeding is main adverse effect Usually weaned off and when

stable onto warfarin (Coumadin)

159

Oral anticoagulantWarfarin (Coumadin)

AKA “rat poison” May also be given IV, but rarely is Bound tightly to plasma protein –

other drugs can displace + other proteins may be present during tissue breakdown (example C- reactive protein)

Very difficult to monitor PT (prothrombin time) and dosed by INR (international normalized ratio)

Long half- life 1 to 3 days

160

Warfarin (Coumadin)

Variable dosing and unpredictable; MUST COME IN FOR FREQUENT MONITORING.

Used prophylaxis for deep vein thrombosis (DVT), Pulmonary Embolus (PE), atrial fibrillation, off label for recurrent Transient Ischemic Attack (TIA), recurrent Myocardial Infarction (MI)

Suppresses coagulation activity by interfering with the production of vitamin K-dependent clotting factors in the liver.

Reduced amount of available Vitamin K for clotting factors II, VII, IX and X

161

Warfarin (Coumadin)

Humans can not synthesize Vitamin K, but bacteria in GI tract can

Treat excessive bleeding with Vitamin K Watch for bruising Careful in older adult because MANY drug

interactions and fall can cause excessive bleeding

Used to prevent clot formation in conditions such as atrial fib, not acute situations

IV Heparin to PO warfarin administer the 2 drugs simultaneously for 2 to 3 days to ensure continuous therapeutic anticoagulation

162

Antiplatelets

Clopidogel (Plavix) & ticlopidine (Ticlid) bind to ADP (adenosine dephosphate) which inhibits its effect on platelets (60 – 70% )

Aspirin inhibits thromboxane (TX2) in Arachidonic Acid Pathway (30-40%)

Abciximab (ReoPro) binds to the GP IIb/IIIa receptor and inhibits platelet aggregation (90%)

Tirofiban (Aggrastat) {new}

163

Antiplatelet Drugs Drug examples:

Aspirin, dipyridamole (persantine), Ticlopidine (Ticlid)

Indications for use: Prophylaxis for thrombo-embolic events Ticlid – second line drug use to prevent stroke in

high risk individuals, decrease intermittent claudication, and decrease graft occlusion after coronary artery bypass

Contraindications: Active bleeding, thrombocytopenia, severe liver

impairment Adverse effects: Bleeding, tinnitus, dizziness,

neutropenia (Ticlid)

164

Thrombolytic Drugs Drug examples:

Alteplase (tissue plasminogen activator) (activase), streptokinase, urokinase

Indications for use: Drugs used to lysis coronary artery

thrombi Alteplase, streptokinase, and urokinase

used to treat PE Streptokinase and urokinase used to

treat DVT and to clear arterial catheters and arteriovenous shunt

MRI needed for CVA to determine cause

165

Thrombolytic Drugs

Contraindications: Recent streptococcal infection, active internal bleeding

Adverse effects: urticaria, fever Nursing responsibilities:

Monitor V/S for bleeding or hypotension, check peripheral pulses to ensure circulation

Keep typed and cross matched blood on hand to administer in case of hemorrhage

Thrombolytic drugs should be administered only when the patient’s hematologic function and clinical response can be monitored

Ensure that aminocaproic acid (Amicar), the antidote for thrombolytic overdose, is readily available

166

Antiplatelet Drugs

Drug examples: Aspirin, dipyridamole (persantine),

Ticlopidine (Ticlid) Indications for use:

Prophylaxis for thrombo-embolic events Ticlid – second line drug use to prevent

stroke in high risk individuals, decrease intermittent claudication, and decrease graft occlusion after coronary artery bypass

Contraindications: Active bleeding, thrombocytopenia, severe

liver impairment Adverse effects: Bleeding, tinnitus, dizzines,

neutropenia (ticlid)

167

Drugs Affecting the Endocrine System

168

Thyroid Hormones

Thyroid replacement increases metabolism, cardiac output, regulates cell growth and causes diuresis. Most commonly used: – thyroid and

levothyroxine (Synthroid) Contraindications: – Recent MI, adrenal

insufficiency, hyperthyroidism Side Effects: – Cardiac dysrhythmias Adverse Effects: – Tachycardia, angina,

hypertension, insomnia, headache, anxiety, increased or decreased appetite, menstrual irregularities, weight loss, heat intolerance (“hot flashes”) and thyroid storm

169

Antithyroid Drugs Used to treat hyperthyroidism

Most commonly used: – methimazole and propylthiouracil which inhibit formation of thyroid hormone

Contraindication: – Drug allergy, avoid in pregnancy if at all possible

Side Effects: – Drowsiness, smoky colored urine, aching

Adverse Effects: – Increased BUN and creatinine, enlarged thyroid, liver and bone marrow toxicity

Interactions:– Increase in activity of anticoagulants

Propranolol (Inderal) (non-selective beta blocker) given to control symptoms before antithyroid drugs work 2-3 weeks

170

Insulin

Replaces insulin not made or made defectively in the body. Indicated primarily for Type I diabetes but

may be used with Type II Requires careful dosing regimen Contraindications: – Drug allergy to

specific product. Adverse Effect: – Hypoglycemia from

overdose, weight gain Interactions: – corticosteroids,

epinephrine, furosemide, phenytoin, thiazides, thyroid hormones, alcohol, anabolic steroids, MAO inhibitors

171

Action of Insulins

Preparation Onset of Action

Peak Action Duration of Action

Humalog

10-15 minutes

30-60 minutes 5 hours or

less

Regular* 30-60 min 2-4 hrs 6-10 hrs

NPH/Lente

1-2 hrs 4-8 hrs 10-18 hrs

Ultralente

2-4 hrs 8-14 hrs 18-24 hrsInsulin glargine (Lantus) - a basal insulin for tighter glycemic control. Do not mix with insulin. May be

used also for type 2 glycemic control.

Regular insulin can be given IV in emergency situations

172

Sliding Scale (Rainbow Coverage)

Regular insulin is given according to blood glucose results. Used mostly with newly diagnosed diabetics

when stress occurs, such as illnesses requiring hospitalization and surgery

Used with blood glucose greater than 200 mg/dl

Example: 4 units = 200 – 250 6 units = 251 – 300 8 units = Greater than 300

May need to call MD – Carefully check order.

173

Classes of agents for Type 2

SULFONYLUREAS 1ST generation 2nd generation

ALPHA-GLUCOSIDASE INHIBITORS BIGUANIDES MEGLITINDES THIAZOLIDINEDIONES INCRETIN MIMETICS (injected, new for

type 2) SYNTHETIC ANALOGS OF AMYLIN

(injected, new (1 & 2) Insulin glargine for tighter control (1 & 2) Inhaled insulin (1 & 2) “EXTRA, EXTRA!

Two new

classes!”

174

Complications of uncontrolled Type 2

Vascular disease especially hypertension

Urinary Tract Infections (UTIs) Vaginitis Prostatitis Retinopathy Nephropathy Nonketotic coma (uncontrolled)

175

Sulfonylureas (secretagogues)- means stimulates the secretion of insulin

First generation EXAMPLE=Diabinese

(chlorpropamide) Potentiated by NSAIDs Highly protein bound P450 system so drug

interactions Hypoglycemia Stimulates pancreas May increase incidence

of increased glucose intolerance

Rarely used today

Second generation EXAMPLE=

Diabeta (glyburide)

Much the same as 1st generation

May increase insulin sensitivity

Also potential hypoglycemia

176

Biguanides

EXAMPLES Metformin (Glucophage XR) & Metformin (Fortamet XR)

Action Decrease hepatic glucose production Increases insulin sensitivity Decreases intestinal absorption of glucose

Improves lipid profile, decreases Triglycerides

DOES NOT produce hypoglycemia Used as monotherapy or combination

therapy

177

Biguanides

New use as prevention of Type II with FBS < 110 mg/dL > 125 mg/dL & History in family

May lower vitamin B12 levels ? Best to supplement

Side effects: Usually good side effect profile, GI symptoms, WEIGHT REDUCTIONDo not give to patients who are being treated for CHF because of possibility of lactic-acidosis

178

Alpha-Glucosidase Inhibitors

EXAMPLES Acarbose (Pecose) Miglitol (Glyset)

Action: Blocks intestinal amylase so delays

breakdown of complex carbohydrates Decreases postprandial glucose

Monotherapy or combination therapy Side effects: are minimal - flatulence,

diarrhea, abdominal cramps

179

Thiazolidinediones

EXAMPLES Pioglitazone (Actos) Rosiglitazone (Avandia)

Action: Reduce insulin resistance Monotherapy or combination with

sulfonylureas, metformin Enhance insulin action in skeletal

muscle, liver and fat tissue Reduce hepatic glucose output Glucose uptake into peripheral

tissue

180

Thiazolidinediones Precautions:

Do not use in patients with hepatic dysfunction

Monitor liver function tests Caution with cardiac patients In combination with other antidiabetic

agents, can cause fluid retention, may exacerbate CHF; caution with insulin use

Side effects: May cause edema and weight gain,

headache, upper respiratory infection Does not cause hypoglycemia when

used as monotherapy

181

Meglitinides (partial secretagogues)

EXAMPLES Repaglidine (Prandin) Taken ½ hour before meals Rapidly absorbed Needs presence of glucose to exert it’s

action Stimulates release of insulin

Side effects: Potential for hypoglycemia, URI

Monotherapy or combination with metformin

182

Amino Acid Derivative a secretagogue

EXAMPLE Naeglinide (Starlix)

Give adjunct with diet & exercise Give to those who have not been treated

chronically with other antidiabetic agents

Take 1 hr. to 30 min. before meals Caution if patient is malnourished Skip dose if meal skipped Contraindicated in Type I and

ketoacidosis Not recommended in pregnancy Monitor when concurrent highly

protein-bound drug given

183

184

Parathyroid hormone (PTH)

Stimulated by low serum calcium Inhibited by normal or high levels of

calcium via negative feedback system Phosphate also regulated by PTH via

an inverse relationship with calcium PTH activates Vitamin D which

increases intestinal absorption Less urinary excretion of calcium Bone reabsorption of calcium from

bone

185

Calcitonin & decreased PTH

Hypercalcemia decreases secretion of PTH

Calcitonin is synthesized in the thyroid Calcium is lost in urine Decreased absorption of calcium from

the intestine Decreased reabsorption of calcium from

bone

186

Vitamin D

In activated form acts like hormone (intermediate metabolism in liver then to active form in kidney called calcitriol)

Obtained from foods and by sunlight on skin

Deficiency limits amount of calcium absorbed from diet

Causes release of calcium from the bone (reabsorption)

Causes G.I. absorption of calcium Decreased levels caused by medications

including tetracyclines and Dilantin

187

Osteoporosis

Risk factors Current low bone mass (DXA) [dual

energy x-ray absorptiometry] Thin, small frame female Advancing age Family history of osteoporosis Estrogen/testosterone deficiency Anorexia nervosa Low lifetime calcium intake History of fracture after age 50 Smoking, alcohol and sedentary life style Use of oral glucocorticoids for chronic

disease

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Drugs used for Calcium/bone Disorders (osteoporosis & osteopenia)

Biphosphonates: alendronate (Fosamax), risedronate (Actonel) new once a month ibandronate (Boniva) used for osteopenia, osteoporosis, Paget’s disease

Action: undergo incorporation into bone. Osteoclasts begin to reabsorb biphosphonate-containing bone so they ingest some of the drug, which then acts to inhibit their activity

All poorly absorbed from GI tract. Take in a.m. with full glass of water, but

without food for 30 minutes and remain in upright position to minimize risk of esophagitis.

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Drugs used for Calcium/bone Disorders (osteoporosis & osteopenia)

Thyroid hormone: Calcitonin (Miacalcin)

•Produced by body when low levels of calcium

•Used to treat osteopenia

•Nasal spray

•Suppresses bone reabsorption

•Main side effect is runny nose and sneezing

•Hormone Replacement Therapy

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Mechanisms that raise serum calcium levels

If decreased Serum Calcium

Parathyroid hormone secretion

renal excretion of calcium

Intestinal absorption of calcium via activation of Vit D

Bone resorption so calcium

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Mechanisms that lower serum calcium levels

If increased Serum calcium

Parathyroid hormone secretion

Calcitonin secretion

Renal excretion of calcium

Intestinal absorption of calcium

Bone resorption

Serum calcium

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Arthritis

Osteoarthritis

Rheummatoid arthritis (RA)

Acute gouty arthritis

Excessive wear & tear of wt. bearing joints

Autoimmune disorder with autoantibodies (rheumatoid factors)

Uric acid crystals accumulate in joints

Often thought as normal part of aging process

Systemic manifestations

Sudden onset, triggered by diet, injury/stress; often big toe

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Corticosteroids There are 2 types – Glucocorticoids

and Mineralcorticoids Cortisol is primary glucocorticoid Aldosterone is primary mineralcorticoid

Some Indications: Replacement therapy for Addison’s

Disease Inflammatory diseases

Arthritis Ulcerative Colitis Nephrotic syndrome Liver disorders Ocular inflammations

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Corticosteroids (cont’d)

o Some indications: (cont’d)o Allergic conditions – status

asthmaticus, asthma, allergic reactions

o Neoplastic diseaseso Brain-injuries (cerebral edema)o Skin conditions (psoriasis/dermatitis)o Collagen disease (Lupus)o Ophthalmic – conjunctivitis, corneal

abrasionso Asthma

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Corticosteroids (cont’d)

Precautions: Therapy is tapered and not discontinued

abruptly Vaccinations are contraindicated Use with caution during pregnancy, lactation,

clients high risk for infections, peptic ulcer disease (PUD), cardiac or renal failure, diabetes, myasthenia gravis

Do not use with fungal or viral eye infections Interactions – Increased risk of:

Hypokalemia with K-depleting diuretics Digitalis toxicity Gastric ulcers with NSAIDS Hyperglycemia

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Estrogen Indications:

Hormone replacement therapy Normal sexual development with estrogen

deficiency Androgen suppression with prostate Ca Oral contraception by inhibiting ovulation

Side Effects: Headache Depression

Adverse Effects: Hypertension Thrombo-embolic disorders Abnormal uterine bleeding Unopposed may lead to endometrial cancer

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Estrogen (cont’d)

Contraindications: Pregnancy and lactation Previous or active thrombo-phlebitis or

embolic disorders Estrogen-dependent Cancers History of CVA or Coronary Artery Disease

(CAD), Breast Cancer, liver disorders Precautions:

Oral contraceptives by diabetics or smokers Interactions: Some anti-convulsants

decrease the effectives of oral contraceptives due to P450 system

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Progentins(not progesterone)

Indications - Oral contraception with estrogen, HRT, endometriosis, dysmenorrhea, uterine bleeding

Adverse Effects: Breakthrough bleeding Impaired glucose tolerance Depression Edema and weight gain

Contraindications: Pregnancy, undiagnosed vaginal

bleeding, Thrombo- phlebitic or embolic disorders, Ca of reproductive organs

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Androgens

Most important is testosterone Uses:

Males – erectile dysfunction, delayed puberty, muscle wasting in AIDS

Females – Endometriosis, fibrocystic breast changes, some menopausal symptoms, advanced breast cancer

Females – increases libido

Adverse Effects: Virilization, hepatotoxicity, edema,

gynecomastia in males

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Androgens (cont’d )

Precautions: Contraindicated in pregnancy and

prostate enlargement Children must have bone growth

evaluated q 6 months Anabolic Steroids – Schedule III

controlled substance (not same as testosterone)

Testosterone Interactions:

Enhance effects of oral anticoagulants, oral hypoglycemics and insulin

Barbiturates and calcitonin interfere with the effects of androgens

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Drugs Affecting the Respiratory System

Photo Source: National Cancer Society, Public Domain, http://visualsonline.cancer.gov/details.cfm?imageid=1775

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Antihistamines

Indications: Various allergic reactions Induce sleep Relieve nausea Prevent motion sickness

Side Effects: Drowsiness Dry mouth and blurred vision

Elderly are at high risk for dizziness, confusion, hypotension, unsteady gait & CNS stimulation - Lower doses due to anticholinergic effects

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Antihistamines (cont’d)

Adverse Reactions: Headache, hypertension, GI distress Drug allergy – anaphylaxis Excessive sedation with other CNS depressants

Contraindications: Narrow angle glaucoma, prostatic hypertrophy,

pregnancy, bladder neck obstruction, PUD Not recommended in bronchitis or pneumonia

because they dry secretions making it difficult for removal.

Interactions: Some antibiotics enhance effects MAOIs inhibit metabolism thus enhancing

effects

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Mode of Action Antitussives

narcotic antitussives directly suppress cough reflex inmedulla of the brain (CNS)

dextromethorphan same mode of action as narcotic

benzonatate anesthetizes ornumbs the cough reflex

Photo Source: Wikimedia Commons, Creative Commons, http://commons.wikimedia.org/wiki/Image:Brain_bulbar_region.svg

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Antitussives

Used to relieve coughs: suppresses cough center in medulla if centrally acting Antitussives containing codeine are

Schedule IV meds. Dextromethorphan, non-opioid

Side Effects for centrally acting: Drowsiness, sedation, dizziness,

restlessness, agitation, euphoria Adverse Effects:

Respiratory depression – antidote opioid toxicity (Narcan)

Hypotension, Tachy or bradycardia Drug allergy - Anaphylaxis

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Drugs Affecting the Respiratory System

Beta-Agonists inhaled - short acting + long acting

Beta-agonists – oral agents Methylxanthines Anticholinergics Antiasthmatics

[cromolyn & nedocromil] Corticosteroids Leukotriene modifiers

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Bronchodilators Used to relax smooth muscles in

bronchi and bronchioles for asthma, bronchitis, emphysema

3 Types of Drugs Adrenergics(beta -2) Xanthines Anticholinergics (given by inhalation)

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Follow step approach guidelines when doing health teaching.

See health care provider at least every 6 months for evaluation.

Identify and list triggers. Keep asthma diary & record

“personal best” from peakflow meter. Record three times a day.

Contact provider if peak flow drops and go to

established plan.

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Step Approach Terms

Step oneMild Intermittent

Step TwoMild Persistent

Step ThreeModerate Persistent

Step FourSevere Persistent

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Beta-AgonistsRescue drugs (short acting)

Used most often During acute phase of asthmatic

attack For COPD acute attack of SOB Quickly reduce airway constriction Are Sympathomimetics Stimulate beta-2 receptors

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Anticholinergics

Corticosteroids

Indirect-acting Agents

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Anticholinergics Controller drugs

Ipratropium bromide = Atrovent

New powder inhaler (not metered dose inhaler) 24 hr. duration & may be superior to atrovent = tiotropium bromide (Spiriva)

NOT for acute attacks!

For maintenance tx of bronchospasms MAINSTAY FOR COPD (when combined

with atrovent is called Combvient – brand name)

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Side Effects of Anticholinergics

Respiratory: Dry mouth or throat and coughing

Gastrointestinal: GI distress

CNS: Headache & anxiety

Mild anticholinergic effects if inhaled – do not use if patient has glaucoma or BPHAtrovent or Combivent inhalers produce serious allergic reactions to those with peanut allergy

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Xanthine BronchodilatorsController agent

Aminophylline *usually I.V. when patient in distress

Theophylline *[examples]aerolate, bronkodyl, elixophyllin,

slo-bid, theobid, theo-dur, theolair, & uniphyl

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Theophylline

Wide variability as to plasma half-life Narrow therapeutic index Unpleasant side effects of anxiety, agitation,

insomnia, tachycardia, palpitations Need to draw blood samples to stabilize

patient on correct dosage to minimize adverse effects

Older adults with liver disease and CHF with pulmonary edema have prolonged half-life

Smokers and children have shorter half-life

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Antibiotic classes:Sulfonamides, Penicillins,

Cephalosporins, Macrolides,Quinolones, Aminoglycosides,

Tetracyclines, GlycycyclinesCarbapenems,

Monobactams, Oxazolidinones Streptogramins, Ketolides &

Glycylcyclines

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Drugs Used to Treat Infections

Drugs for treating infections are referred to as antibiotics (most common term) or anti-infectives, antimicrobial

Antibiotics are not effective against viruses

Resistance is the BIG PROBLEM

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Anti-infectives General Action

Types of antibiotic

action

Damages the cell

wall

Modifies

protein synthe

sis

Modifies

DNA synthe

sis

Modifies energy

metabolism via

folic acid

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AntibioticsActions

Inhibit the growth of bacteria Inhibit cell wall synthesis Are bacteriostatitic and bacteriocidal

Adverse Reactions: Some are very nephrotoxic Hearing impairment- ototoxic Superinfections May potentiate decreased effectiveness of other medications (Be aware of specific interactions with specific drugs) “Sunburn” reaction – Avoid direct sunlight with tetracyclines

Contraindications: Known drug allergy Many should not be used during pregnancy

Many resistance patterns

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Penicillin resistance

Penicillinases (enzymes) produced by bacteria that destroy penicillin by cleaving the beta-lactam ring of the drug

Clavulanic acid enhances the activity of penicillins. Binds to the active sites of penicillinases rendering the enzyme inactive

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Some Commonly Used Antibiotics

Sulfonamides One of the first anti-infectives Often used today for Urinary Tract

Infections Drink fluids to prevent urinary crystals

Septra Bactrim

Assess allergy to other sulfa medications (Sulfonylureas,Thiazide diuretics)

Penicillins Penicillin G, Ampicillin, Amoxicillin Observe for clostridium difficule Fruit juices can inactivate the drug Assess electrolytes

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Some Commonly Used Antibiotics (cont’d)

Tetracyclines (not with milk, CA products)

Take one hour before or two hours after meal Causes brown teeth in children! Photosensitivity

Macrolides – Erythromycin and Biaxin can have many drug interactions, problems with G.I. distress

Used to treat mycoplasma (penicillins & cephalosporins not effective!)

Used when patient is allergic to penicillin Use cautiously with heart, renal, liver disease Not given with fruit juice

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Cephalosporins

•Similar to PCN but broader spectrum

•Differ as to generation for coverage. When anaphylaxic reaction to PCN, should not be given a cephalosporin

•A beta-Lactam antibiotic

•May be ineffective against bacteria that produce

enzyme beta-lactamase

•Called cephalosporinase

•Avoid alcohol. Also, now may not be effective against MRSA

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Quinolones

Kill bacteria = bactericidal Active on a wide variety of bacteria

gm- & gm+ as well as a-typical infections Excellent oral absorption Antacids reduce their absorption * gm- coverage & excellent [drug] for

kidneys Great for treating UTI’s & prostatitis first

oral class of antibiotic to kill gram- bugs Good for Salmonella typhi and Shigella Not used in children. May damage

cartilage, leading to deformities in gait

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Quinolones

Used to treat: lower respiratory tract infections bone & joint infections infectious diarrhea urinary tract infections skin infections

Overuse! They should be reserved for serious infections and resistant strains. MRSA can be susceptible. Do not want to create resistance

Should not be used in children - may damage cartilage leading to deformities in gait

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Aminoglycosides

Used to Treat:Pneumonias, resistant UTIs, septicemia, CNS infections – serious & life threatening

Action:Bind to 30S & 50S ribosomal subunitsCause inhibition of protein synthesis

Precautions:Nephrotoxicity & ototoxicity (8th cranial nerve) Drug levels help prevent high peaks & troughs, many drug interactions; must monitor carefully.

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Miscellaneous antibiotics

Vancomycin Rapidly bactericidal so low resistance Glycopeptide antibiotic not related to PCNs Given by intermittent IV infusion Used in life-threatening staph or strep

infections and MRSA Adverse reactions are nausea, flushing and

itching Red Man Syndrome

Toxic reactions: tinnitus, hearing loss, nephrotoxicity

Often given with piperacillin (Zosyn) IV a broad spectrum PCN + B-lactamace inhibitor for MRSA

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Ethambutol (Myambutol) RARE retrobulbar neuritis & blindness GI upset

INH isoniazid (Nydrazid) Peripheral neuritis & rarely

hepatotoxicity Don’t give for prophylaxis after age 40 because of increase in side effects Peripheral neuropathy Selegiline (SEL)-like syndrome

Pyrazinamide Hepatotoxicity & hyperuricemia (reports of liver failure)

Rifampin Hepatitis, body fluids turn orange/red color

Streptomycin

Antituberculars

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Latent TB

If skin test is positive Follow up with chest x-ray

Use INH for 9 months or rifampin for 4 months for latent TB

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Antifungal Agents = drug interactions + liver toxicity

Itaconazole (Sporanox): inhibitor of cytochrome 3A4 = increased statins, Ca + channel blockers, some Benzodiazipines, etc.

Ketoconazole (Nizoral): inhibitor of cytochrome 2C19 = increased levels of phenytonin, some Tricyclic Antidepressants, some Benzodiazipines, etc.

Fluconazole (Diflucan): inhibitor ofcytochrome 2C9 = increased level of celebrex, NSAIDs, Warfarin, phenytoin, etc.

Examples of systemic antifungals

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Antivirals

Drugs used to kill viruses Inhibit their ability to replicateDifficult to kill because they live inside our

cells Utilize our cells to replicate

Any drug that kills a virus may kill our cellsOnly work during viral replicationMutations & resistance commonAntimicrobials not effective unless

accompanying secondary bacterial infection

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Photo Acknowledgement:Unless noted otherwise, all photos

and clip art contained in this module were obtained from the

2003 Microsoft Office Clip Art Gallery.