CHAPTER CONTENTOverview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 862

Drug Laws. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 862

Drug Standards. . . . . . . . . . . . . . . . . . . . . . . . . 863

Drug References. . . . . . . . . . . . . . . . . . . . . . . . 864

Vocabulary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 865

Word Elements. . . . . . . . . . . . . . . . . . . . . . . . . 869

DrugSources. . . . . . . . . . . . . . . . . . . . . . . . . . . 871

DrugNames. . . . . . . . . . . . . . . . .. . . . . . . . . . 871

DrugActions/Interactions. . . . . . . . . . . . . . . . 872

Routesof Administration for Medications. . . . 874

Drug Classification. . . . . . . . . . . . . . . . . . . . . . 877

Common Charting Abbreviations. . . . . . . . . . 881

Written and Audio Terminology Review. . . . . 882

ChapterReviewExercises. . . . . . . . . . . . . . . . . 885

Answers to Chapter Review Exercises. . . . . . . . 893

KEY COMPETENCIESUpon completing this chapter and the review exercises at the end of the chapter, the learner should be able to:

1. Identify the laws and governing agencies that enforce the safe manufacture, distribution, and use of foods, drugs,and cosmetics.

2. List five drug schedules used for categorizing controlled substances as identified in this chapter.

3. List four drug referenc~s identified in this chapter.

4. Identify four sources of drugs, giving examples for each source, as identified in this chapter.

5. Identify five different names given to drugs to identify either their chemical formula, their manufacturer's originalname, or the name under which they are sold.

6. Identify at least 10 drug actions/interactions that occur within the body.

7. Identify 10 different forms of administration of medications.

8. Identify at least 14 classifications of drugs identified in this chapter.

9. Correctly spell and pronounce each new term introduced in this chapter using the Activity CD-ROM and AudioCD, if available.

10. Identify at least 30 abbreviations related to pharmacology.

861

862 . CHAPTER22

OVERVIEWHealth care professionalsmust know the basicsof pharmacologyand understandthe interactions of drugs within the body. A knowledgeof the sources,forms,routes of administration, classifications, indications, range of dosages,desiredeffects, and side effects of drugs is essential.Additionally, health care profession-als must knowthe laws regulating the distribution and useof medications.A con-centrated study of pharmacology will provide the background necessaryforunderstandingthe needfor safeadministration of medicationsasprescribedbythephysician, and for acquiring a strong senseof responsibility concerningadminis-tering medications.

Pharmacologyis the field of medicinethat specializesin the study of drugs,theirsources,appearance,chemistry, actions, and uses.A drug is any substancethat,when taken into the body, may modify one or more of its functions.Pharmacodynamicsis the study of how drugsinteract in the humanbody.A phar-macist is one who is licensedto prepareand dispensedrugs.A pharmacyis a drug-store. Chemotherapyis the study of drugs that have a specific and deadlyeffecton disease-causingmicroorganisms.Thesedrugsare usedin the treatment of cer-tain infectious diseasesand cancer.Toxicologyis the study of poisons,their detec-tion, their effects, and establishing antidotes (substancesthat opposethe actionof poisons) and methodsof treatment for conditions they produce.

Thereare manyterms related to pharmacology.Health care professionalsmayusethese terms on a day-to-day basis when involved in administering medications,instructing patients in the useof medications,charting the administration of med-ications, or transcribing information regarding medicationsin the patient's chart.This chapter is devoted to the study of terms that relate to the field of pharma-cology. Whereappropriate throughout the chapter, word elementswill be identi-fied and defined.

Drug LawsTo ensure the safe manufacture, distribution, and use of medications, drugs are sub-ject to numerous state and federal laws. The Food, Drug, and Cosmetic Act (FDCA)was passed in 1938. This law regulates the quality, purity, potency, effectiveness, safety,labeling, and packaging of food, drug, and cosmetic products. The government agencyresponsible for administering and enforcing the FDCA within the United States is theFood and Drug Administration (FDA). The federal law concerned with the manufac-ture, distribution, and dispensing of controlled substances, those drugs that have thepotential of being abused and of causing physical or psychological dependence,administering, and enforcing the Controlled Substances Act is the Drug EnforcementAdministration (DEA). Physicians who administer controlled substances must entertheir DEA number on the prescription. Drugs that fall under the ControlledSubstances Act are known as controlled substances or schedule drugs. These drugsare identified by a classification system that categorizes them by their potential forabuse. The schedule is divided into five categories: Schedules I to V. The five schedules.for controlled substances are listed in Table 22-1 with examples of specific medicinesappearing in each schedule.

Table 22-1 Schedule of ControlledSubstances

DRUGSCHEDULE DESCRIPTION

I

II

III Schedule III drugs have moderate potentialfor abuseor

physicaldeordered bytelephone order. Pmonths. Theymaynthan five times in a 6-month period.

v

bythere is no limit on

Someof these drugs may

PHARMACOLOGY. 863

EXAMPLE DRUGS

Tylenolwith codeine,butisol,hycodan

Librium,valium,darvon,

equaniL

Robitussin A-C,

donnagel-PG,lomotil

*Limited special permission has been obtained in some states for MDs to prescribe marijuana fortreatment of side effects, such as nausea and vomiting, in patients receiving chemotherapy.

Drug StandardsThe law requires that all preparations called by the same drug name must be of a uni-form strength, quality, and purity. This assures the patient of getting the same quality,purity, and strength of medication from the pharmacy each time it is prescribed andanywhere in the United States that it is prescribed. These rules, or standards, have beenestablished to control the strength, quality, and purity of medications prepared by various

864 . CHAPTER22

manufacturers. The United States Pharmacopeia/National Formulary (USP/NF) is an

authorized publication of the United States Pharmacopeial Convention, Inc. It contains

formulas and information that provide the standard for preparation and dispensation ofdrugs. The USP/NF is recognized by the U.S. government as the official listing of stan-

dardized drugs in the United States. The FDCA specifies that a drug is official when it is

listed in the USP/NF. This publication is updated every 5 years.

Drug ReferencesThere are several reference books available to physicians, nurses, and other health careprofessionals who are responsible for the safe administration of medications. These ref-erences normally provide the following information about drugs listed within them:composition, action, indications for use, contraindications for use, precautions, sideeffects, adverse reactions, route of administration, dosage range, and what forms areavailable.

The Hospital Formulary is a reference listing of all the drugs commonly stocked in thehospital pharmacy. This reference provides information about the characteristics ofdrugs and their clinical usage. This information is continuously revised to provide themost up-to-date information available.

The Physicians' Desk Reference (PDR) is published yearly by Medical EconomicsCompany. See Figure 22-1.

Manufacturers pay to list information about their products in the PDR. The informa-tion provided by the manufacturers is the same basic information that is found in pack-age inserts that accompany each container of medication. The FDA requires that the

-- --~*

~

.-,

.. ~

Figure 22-1 Physicians' Desk Reference (PDR)

PHARMACOLOGY. 865 \.~

drug's generic name, indications, contraindications, adverse effects, dosage, and route of \administration be described in package inserts. Four additional references published bythe Medical Economics Company are as follows:

1. Physicians' Desk Reference for Nonprescription Drugs

2. Physicians' Desk Reference for Ophthalmology

3. Drug Interactions and Side Effects Index

4. Indications Index

The Drug Facts and Comparisons is a reference for health care professionals. It isissued yearly and is updated monthly. This loose-leaf binder reference provides infor-mation on drugs according to their therapeutic classifications. It contains the samebasic facts as the other drug references listed and is particularly helpful in comparingthe various drugs within each category to other products in reference to effectiveness,content, and cost.

q

WORD

VocabularyThe following vocabulary words are frequently used when discussingpharmacology.

DEFINITION

adverse reaction

anaphylactic shock(an-ah-fih-LAK-tic SHOCK)

The body's reaction to a drug in an unexpected way that may endan-ger a patient's health and safety.

A life-threatening, hypersensitive reaction to food or drugs. Thepatient experiences acute respiratory distress,hypotension, edema,tachycardia, cool pale skin, cyanosis, and possibly convulsions shortlyafter administration of the medication.

bacteriostatic.bacteri/o= bacteria

Stopping or controlling the growth of bacteria.

brand name The name under which the drug is sold by a specific manufacturer.This name is owned by the manufacturer and no other company mayuse that name. Each brand name carries a registered trademarksymbol.

buccal medication

(BUCK-al med-ih-KAY-shun)bucc/o = cheek

-al = pertaining to

Medication that is placed in the mouth next to the cheek, where it isabsorbed into the mucous membrane lining of the mouth.

chemical name

chemotherapy(kee-moh- THAIR-ah-pee)

chem/o = chemical reaction

-therapy = treatment

The chemical name for a drug is the description of the chemicalstructure of the drug. It is listed in the Hospital Formulary along withthe chemical formula diagram.

The treatment of diseases using drugs that have a specific deadly effecton disease-causing microorganisms. These drugs are used in the treat-ment of certain infections and cancer.

866 . CHAPTER22

contraindication

(kon-trah-in-dih- KAY-shun)Any special symptom or circumstance that indicates that the use of a

particular drug or procedure is dangerous, not advised, or has not

been proven safe for administration.

Controlled Substances Act

Drugs that have a potential for abuse. These drugs are placed into fivecategories ranging from Schedule I drugs, which are the most danger-ous and most likelyto be abused, to Schedule V drugs, which are theleast dangerous and least likelyto be abused; also known as scheduledrugs.

The federal law concerned with the manufacture, distribution, and

dispensing of controlled substances. These drugs have the potential ofbeing abused and of causing physical or psychologicaldependence.

controlled substances

desired effect

Cumulation means that a drug levelbegins to accumulate in the bodywith repeated doses because the drug is not completely excreted fromthe body before another dose is administered.

The effect that was intended; that is, if the drug lowered the bloodpressure as was intended, the desired effectwas achieved.

cumulation

(KYOO-mew-Iay-shun)

drug Any substance that, when taken into the body, may modify one ormore of its functions.

drug action Drug action describes how a drug produces changes within the body.

Drug effect describes the change that takes place in the body as aresult of the drug action.

drug effect

Drug EnforcementAdministration

The government agency responsible for administering and enforcingthe Controlled Substances Act.

Drug Facts andComparisons

A reference book for health care professionals that provides informa-tion on drugs according to their therapeutic classifications. This refer-ence compares the various drugs within each category with otherproducts.

druggist

first dose

Pharmacist.

Initial dose.

first-dose effect An undesired effect of a medication that occurs within 30 to 90 min-utes after administration of the first dose.

Food,Drug,andCosmetic Act

The government agency responsible for administering and enforcingthe Food, Drug, and Cosmetic Act within the United States.

A law that regulates the quality, purity, potency, effectiveness, safety,labeling, and packaging of food, drug, and cosmetic products.

Food and DrugAdministration

Hospital Formulary(FORM-yoo-lair-ee)

The name that is established when the drug is first manufactured. This

name is protected for use only by the original manufacturer for aperiod of 17 years; after that time, the name of the drug becomes pub-lic property and can be used by any manufacturer.

A reference book that lists all of the drugs commonly stocked in the

hospital pharmacy. This book provides information about the charac-teristics of drugs and their clinical usage.

generic name(jeh-NAIR-ik)

hypotension(high-poh- TEN-shun)

hypo- = under, below,beneath, less thannormal

PHARMACOLOGY. 867

Low blood pressure; less than normal blood pressure.

idiosyncrasy(id -ee-oh -SIN -krah -see)

inhalation medication

(in-hah-LAY-shun)

An unusual, inappropriate response to a drug or to the usual effectivedose of a drug. This reaction can be life threatening.

Medication is sprayed or breathed into the nose, throat, and lungs. Itis absorbed into the mucous membrane lining of the nose and throatand by the alveoliof the lungs.

initial dose The first dose of a medication.

intradermal medication

(in-trah-DER-mal)intra- = withinderm/o = skin

-al = pertaining to

Medication that is inserted just beneath the epidermis using a syringeand needle.

intramuscular medication

(in -trah -MUSS- kyoo-lar)intra- = withinmuscul/o = muscle

-ar = pertaining to

Medication that is injected directly into the muscle.

intravenous medication

(in -trah -VEE- nus)intra- = withinven/o = vein

-ous = pertaining to

Medication that is injected directly into the vein, entering the bloodstream immediately.

local effect A response to a medication that is confined to a specificpart of thebody.

maintenance dose The dose of a medication that will keep the concentration of the med-ication in the bloodstream at the desired level.

official name Generic name.

package insert An information leaflet placed inside the container or package of pre-scription drugs. The FDArequires that the drug generic name, indica-tions, contraindications, adverse effects,dosage, and route ofadministration be described in the leaflet.

parenteral medication(par-EN-ter-al)

Medication that is injected into the body using a needle and syringe.

pharmacist(FAR-mah-sist)

pharmac/o = drugs, medicine-ist = specialist

One who is licensed to prepare and dispense drugs; also known as adruggist.

pharmacodynamics(far-mah-koh-dye-NAM -iks)

The study of how drugs interact in the human body.

'''~''''''C''~ ~, h,~

868 . CHAPTER22

pharmacology(far- mah-KALL-oh -jee)

pharmac/o = drugs,medicine-logy = the study of

The field of medicine that specializes in the study of their sources,appearance, chemistry, actions, and uses. '

pharmacy(FAR-mah-see)

Drugstore.

Physicians' Desk Reference A reference book that provides the same information that is found inpackage inserts that accompany each container of medication:description of the drug, actions, indications and usage (why medica-tion is prescribed), contraindications, warnings, precautions, adversereactions, overdosage, and dosage and administration.

potency(POH-ten-see)

Strength.

potentiation(poh-ten-she-AY -shun)

The effect that occurs when two drugs administered together producea more powerful response than the sum of their individual effects.

rectal medication

(REK-tal)recti 0 = rectum

-al = pertainingto

Medication that is inserted into the rectum and is slowly absorbedinto the mucous membrane lining of the rectum. It is in the form of asuppository, which melts as the body temperature warms it.

route of administration

side effect

The method of introducing a medication into the body.

An additional effect on the body by a drug that was not part of thegoal for that medication. Nausea is a common side effect of manydrugs.

standards Rules that have been established to control the strength, quality, andpurity of medications prepared by various manufacturers.

subcutaneous medication

(sub- kyoo- TAY-nee- us)sub- = under, belowcutane/o = skin

-ous = pertaining to

Medication that is injected into the subcutaneous layer, or fatty tissue,of the skin.

sublingual medication(sub-LING-gwal)

sub- = under

lingu/o = tongue-al = pertaining to

Medication that is placed under the tongue, where it dissolves in thepatient's saliva and is quickly absorbed through the mucous mem-brane lining of the mouth.

systemic effect(sis-TEM-ik effect)

A generalized response to a drug by the body. The drug has a wide-spread influence on the body because it is absorbed into the blood-stream.

tachycardia(tak -ee- KAR-dee-ah)

tachy- = rapidcardi/o = heart

-ia = noun ending

Rapid heartbeat, over 100 beats per minute.

PHARMACOLOGY. 869

therapeutic dose(thair-ah-PEW-tik)

The dose of a medication that achieves the desired effect.

tolerance

(TALL-er-ans )The body's resistance to the effect of a drug.

topical medication(TOP-ih-kal)

Medication that is applied directly to the skin or mucous membranefor a local effect to the area.

toxicology(tocks-ih- KALL-oh-jee)

toxic/o = poisons, toxins-logy = the study of

The study of poisons, their detection, their effects, and establishingantidotes and methods of treatment for conditions they produce.

trade name Brand name.

United States Pharmacopeia(far-mah-koh-PEE-ah)

An authorized publication of the United States PharmacopeialConvention, Inc. that contains formulas and information that providea standard for preparation and dispensation of drugs. Recognized bythe U.S. government as the official listing of standardized drugs.

Medication that is inserted into the vagina; may be in the form of asuppository, cream, foam, or tablet.

vaginal medication(VAJ-in-al)

vagin/o = vagina-al = pertaining to

Word ElementsThe following word elements pertain to pharmacology. As you review thelist, pronounce each word element aloud twice and check the box after you"say it." Write the definition for the example word given for each wordelement. You may use your medical dictionary.

MEANING

sensitivity to pain

against

rhythm

life

WORDELEMENT PRONUNCIATION "SAY IT"

alges/o al-JEE-soh 0analgesic an-al-JEE-sik

-----anti- AN-tih 0antidepressant an -tih -dee-PRESS-ant

arrhythm/o ah-RITH-moh 0antiarrhythmic an -tee-ah -RITH -mik-----

bilo BYE-oh 0antibiotic an-tih-BYE-ot-ik-

bronch/o BRONG-koh 0 airwaybronchodilator brong-koh-DYE-Iay-tor

bucc/o BUCK-oh 0 cheekbuccal BUCK-al

870 . CHAPTER22

chem/o

chemotherapy

KEE-moh

kee-moh- THAIR-ah-pee

D drug

oo ~ "" ""

clotting

-----

coagul/oanticoagulant

cutane/osubcutaneous

cyan/ocyanosis

esthesi/oanesthesia

fung!oantifungal

gloss/ohypoglossal

koh-AG-yoo-Iohan-tih-koh-AG-yoo-Iant

D

_00 "_.----'--'---"-

kyoo- TAY-nee-oh

sub-kyoo-TAY-nee-us

D skin

'__.'_00._-' "

sigh-AN-oh

sigh-ahcNOH-sis

D blue

-.----.-----.-----

ess-THEEZ-ee-ohan-ess- THEEZ-ee-ah

D feeling, sensation

--'-' ' '00 00'_-

FUNG-oh

an-tih-FUNG-al

D fungus

"'-" "-"'-

GLOSS-oh

high -poh -GLOSS-al

D tongue

""~~~._-------_.__._._.__._.._-_._--_....__._-

excessive, highhyper-antihypertensive

hypno-hypnotic

-ia

analgesia

immun/o

immunosuppressant

intra-intradermal

-ist

pharmacist

lingu/o

sublingual

lip/olipid

-logypharmacology

HIGH-per

an-tih-high-per- TEN -siv

D

' '-'.'-' "--------

HIP-noh

hip-NOT-ik

D sleep

---.-.---..--------------

EE-ah

an -al- JEE-see-ah

D condition; noun

ending------

IM-yoo-noh

im -yoo- noh-suh -PRESS-ant

D immune, protection

00.____-

IN-trahin-trah-der-mal

D within

-,-,---"---'-------

1STFAR-mah-sist

D a specialist in a fieldof study

0._--_._--------- ---------

LlNG-yoo-ohsub-LlNG-gwal

D tongue

----.--.-.--.------.--..---

LlP-ohLlP-id

D fat

---.--.----.----.--...---..--..--

LOH-jeefar-mah-KALL-oh-jee

D the study of

.--.----.------------..museui/ointramuscular medication

MUSS- kyoo-Iohin -trah -MUSS- kyoo-Iar

D muscle

.--------------..-.-----.------..-....-----------....---newne/o

antineoplastic

NEE-ohan- tih-nee-oh- PLASS-tic

D

".-----.-.-----.-------------.

PHARMACOLOGY. 871

or/ooral medication

OR-ohOR-al

D mouth

pharmac/o

pharmacy

FAR-mah-koh

FAR-mah-seeD drugs, medicine

rect/orectal medication

REK-tohREK-tal

D rectum

skelet/oskeletal muscle relaxant

SKELL-eh-toh DSKELL-eh-tal muscle rih-LAK-sant

skeleton

sub~

subungual

SUB

sub-UNG-gwal

D under, below

------

toxic/o

toxicology

TOCKS-ih-koh

tocks-ih-KALL-oh-jee

D pOlson

----

vaginlo

vaginal medication

VAJ-in-ohVAJ-in-al

D vagma

----------------

ventointravenous

VEE-nohin-trah-VEE-nus

D vem

Drug SourcesThe origin of many of the drugs used today can be traced to ancient civilizations. Manydrugs were prepared from plants, leaves, herbs, roots, and barks, with plants being a pri-mary source of medicinal substances. Examples of plant sources of medications are thepurple fox glove, which is a source for digitalis, a medication used to treat heart arrhyth-mias and congestive heart failure, and the poppy plant, which is a source of opium, andis used in antidiarrheal medications and analgesics. Leaves and herbs were sources ofmedicinal-type teas in the earlier generations.

As time evolved, animals and minerals became additional sources of drugs. An exampleof an animal source for drugs commonly used today is insulin, which is extracted fromthe pancreas of animals (hogs and cows). An example of a mineral source of drugs is sul-phur, which is used in many bacteriostatic medications.

A more recent source of drugs has been pharmaceutical laboratories that produce syn-thetic drugs. Medications such as Demerol, a narcotic analgesic, and Lomotil, anantidiarrheal, are examples of synthetic forms of medications. Insulin and sulphur drugsare also produced synthetically in pharmaceutical laboratories. See Figure 22-2.

-

Drug NamesThe chemical name of a drug describes the chemical structure of the drug. It is the for-mula that indicates the composition of the drug.

The generic name or officialname of a drug is the name that was established when thedrug was first manufactured. The spelling of the generic name is written in lowercase

872 . CHAPTER22

~

pancreas ofcow, hog

thyroid glandof animals

meperidine Demerol analgesic

diphenoxylate Lomotil antidiarrheal

Figure 22-2 Drug sources

letters. The original manufacturer of the drug is the only company that can use thegeneric name for the drug for the first 17 years of its use; then the name of the drugbecomes public property and can be used by any manufacturer. Each drug has only onegeneric name. The official (generic) name for each drug is listed in the USP/NF.

The brand name or trade name of a drug is the name under which the drug is sold by aspecific manufacturer. The name is owned by the drug company and no other companymay use that name. Each brand nam.e drug carries a registered trademark symbol (@)after its name, showing that it is restricted to the particular manufacturer. A drug maybe known by several different brand names. The spelling of the brand name or tradenamealwaysbeginswith a capital letter.

-..---...-...----..----.-.-...--...--

Drug Actions/InteractionsWhen drugs are ingested or administered into the body, they are absorbed into thebloodstream or into the body tissues. The drugs then combine with, or alter, the mole-cules in the body cells, changing the way the cells work. How the drugs produce thesechanges within the body is known as drug action. The changes that take place in thebody as a result of the drug action is known as the drug effect. Some drugs act in thebody by either slowing down or speeding up the ordinary processes that the cells carryout. Other drugs destroy certain cells or parts of cells, such as drugs that destroy disease-producing microorganisms and cancer cells. Yet other drugs act by replacing substancesthat the body lacks or fails to produce, such as vitamins.

Source Example Drug name Classification

cinchona bark quinidine antiarrhythmic

purple foxglove I digitalis cardiotonic

magnesium

I

Milk of Magnesia antacid, laxative

gold Solganal; anti-inflammatoryauranofin used to treat

rheumatoidarthritis

insulin I antidiabetichormone

thyroid, USP I hormone

The effect of the drug in the body may be a desired effect, achieving the response by thebody that is intended; that is, the desired effect was to lower the blood sugar, and thepatient's blood sugar level did drop. A drug is usually prescribed for its desired effect. Aside effect, is an additional effect on the body by the drug that was not part of the goalfor that medication; nausea is a common side effect of many drugs. Even though sideeffects are bothersome, they are not usually severe enough to warrant discontinuing themedication. An adverse reaction is one in which the body reacts to a drug in an unex-pected way that may endanger a patient's health and safety. A contraindication is anyspecial symptom or circumstance that indicates that the use of a particular drug or pro-cedure is dangerous, not advised, or has not been proven safe for administration.

Drugs may affect only a specific part of the body, having a local effect, or they may affectthe body as a whole, having a systemic effect. A local effect of a drug is one that is con-fined to a specific part of the body; for example, the dentist may administer a medica-tion to numb only one tooth, thus, the medication has a local effect on that particulararea of the body.

A systemic effect of a drug is one that has a widespread influence on the body because itis absorbed into the bloodstream. The remaining terms in this section describe theaction and interaction of drugs in the body after they have been absorbed into thebloodstream; that is, those having a systemic effect on the body.

cumulation

(KYOO-mew-Lay-shun)

idiosyncrasy(id-ee-oh-SIN-krah-see)

Cumulationoccurs when a drug is not completely excreted from thebody before another dose is given.

When repeated doses of the drug are given, the drug starts to accumulatein the body tissues and toxic effects may occur.

-------An idiosyncracy is an unusual, inappropriate response to a drug orto the usual effective dose of a drug.

This reaction may be life threatening. An example of a severe idiosyncraticreaction to a drug or its dosage is anaphylactic shock in which the patientexperiences acute respiratory distress, hypotension, edema, tachycardia,cool pale skin, cyanosis, and possibly convulsions shortly after administra-tion of the medication; penicillin is a medicine that is known to cause ana-phylactic reactions in some individuals.

potentiation(poh-ten-she-AY-shun)

Potentiation occurs when two drugs administered together producea more powerful response than the sum of their individual effects.

Patients who are taking blood thinners are advised to avoid taking aspirin,which will potentiate the thinning effect on the blood.

tolerance

(TALL-er-ans)

Tolerance is resistance to the effect of a drug.

The individual develops a decreased sensitivity to subsequent doses of thedrug and requires increasinglylarger doses to get the full effectof the drug.Tolerance is also a characteristic of drug addiction.

When a drug is given for the first time by whatever method, it is called theinitial dose. The initial dose is also known as the first dose. Sometimes

874 . CHAPTER22

....

patients will have an undesired effect after the initial or first dose of a med-ication, particularly with some medications given for treatment of hyper-tension; that is, a sharp drop in blood pressure and fainting within 30 to90 minutes after the first dose of the medication. This response to the ini-tial dose of a medication is known as first -dose effect.

The dose of a medication that achieves the desired effect is known as the

therapeutic dose. Some medications have to be given in increasing dosesuntil the desired level of concentration in the bloodstream is achieved. A

maintenance dose will keep the concentration of the medication in thebloodstream at the desired level. Medications given to slow and strengthenthe heartbeat are often given in increments until the maintenance doselevel is achieved.

Routes of Administrationfor MedicationsMedications can be introduced into the body using several different meth-ods, referred to as the route of administration. The route of administra-

tion determines how rapidly a drug is absorbed into the bloodstream, howwell the drug is absorbed, and how long the drug acts within the body. Theroute of administration is usually based on the type of medication given,the dosage form, and the desired effect. The following is a list of the majorroutes of administration for medications. The list is not alphabetized, but

is presented in the order in which routes of administration of medicationsare usually discussed in pharmacology textbooks.

oral

(OR-aL)orjo = mouth-aL = pertaining to

sublingual(sub-LING-gwaL)

sub- = under, beLow

Lingujo = tongue

-aL = pertaining to

An oral medication is one that is given by mouth and swallowed.

This drug is then slowlyabsorbed into the bloodstream through the liningof the stomach and intestines. See Figure 22-3.

Advantage: easiest and safest method, most economical method.

Disadvantage: slow method of absorption, possibility of being destroyedby the gastric juices.

Figure 22-3 Oral medications

Asublingual medication is one that is placed under the tongue.

It dissolves in the patient's saliva and is quickly absorbed through themucous membrane lining of the mouth; also known as hypoglossal.

Advantage: more rapid absorption rate than oral, higher concentration ofmedication reaches the bloodstream by not passing through the stomach.

Disadvantage: not a convenient route of administration for bad-tastingmedications or those that might irritate the mucous membrane.

PHARMACOLOGY. 875

buccal

(BUCK-al)

buee/o = cheek

-aL = pertaining to

A buccal medication is one that is placed in the mouth next to thecheek; it is in tablet form.

The medication is absorbed into the mucous membrane lining of themouth.

Advantage: more rapid absorption rate than oral, higher concentration ofmedication reaches the bloodstream by not passing through the stomach,effects of the medication stop if the tablet is removed.

Disadvantage: possibility of swallowingthe pill.

inhalation

(in-hah-LAY-shun)Medicationsadministered by inhalation are th~se that are sprayedor inhaled into the nose, throat, and lungs. See Figure22-4.

The medication is absorbed into the mucous membrane lining of the noseand throat and by the alveoliof the lungs. These drugs are in the form ofinhalers, sprays, mists, and sometimes steam vapor.

Advantage: good absorption due to large surface contact area, providesrapid treatment.

Disadvantage: sometimes difficult to regulate the dosage, not suitable formedications that might irritate the mucous membrane lining, sometimesconsidered to be an awkward method of administering medication.

Figure 22-4 Medicationsby inhalation

rectal

(REK-tal)reet/o = rectum-aL = pertaining to

Rectalmedications are those that are inserted into the rectum andare slowlyabsorbed into the mucousmembranelining of the rectum.

This medication is in the form of a suppository, which dissolves as thebody temperaturewarmsand meltsit. SeeFigure22-5A.

Advantage: one method of choice when the patient is nauseated or cannottake medications orally.

Disadvantage: absorption is slow and irregular.

Figure 22-5 (A) Rectal medications; (B) vaginal medications

876 . CHAPTER22

vaginal(VAJ-in-al)

vaginjo = vagina-al = pertaining to

topical(TOP-ih-kal)

transdermaltrans- = across

dermjo = skin-al = pertaining to

.--------.---.---------------...

Vaginal medications are those that are inserted into the vagina.

This medication may be in the form of a suppository, cream, foam, ortablet. The medication dissolves as the body temperature warms and meltsit. See Figure 22-58. Vaginal medications are usually given for their localeffect on the mucous membrane lining the vagina.

Advantage: easiest method for treating the specific area.

Disadvantage: no particular disadvantage, other than the fact that med-ications sometimes stain underwear.

A topical medication is one that is applied directly to the skin ormucous membrane for a local effect to the area.

These medications are in the form of creams, ointments, sprays, lotions,

liniments, liquids, and powders.

Advantage: easy method, convenient.

Disadvantage: slow absorption through the skin.

A methodof applyinga drugto unbrokenskin.Thedrugisabsorbedcontinuouslyand producesa systemiceffect.

Medications administered by the transdermal infusion system are packaged inan adhesive-backed disk. The disk contains a premeasured amount of med-ication. When the disk is applied, the medication is released through the skininto the bloodstream at a controlled rate, producing a systemic effect.Examples of transdermal medications include vasodilators such as nitroglyc-erin, hormones such as estrogen, and medications used to help stop smoking.

Advantage: good method for administering medications that need to bereleased slowly into the bloodstream over a period of time.

Disadvantage: units can be dangerous if they come in contact with the skinof children or pets. There are a very limited number of drugs available atthis time that can be administered by the transdermal patch. Removal of

the patch does not guarantee immediate stoppage of absorption of themedication, should an adverse reaction occur. See Figure 22-6.

Figure 22-6 Transdermaldeliverysystem

parenteral

(par-EN-ter-al)

par-= apartfromenterjo = intestine-al = pertaining to

----------

Parenteralmedications are those administered by injecting the med-ication into the body using a needle and syringe. See Figure 22-7.

Parenteral medication must be in a liquid form and is administered by one

of the following four methods.

intradermal

(in-trah-der-mal)intra- = within

dermjo = skin-al = pertaining to

A small amount of medication is injected just beneath theepidermis.

Intradermal injections are used for allergy testing, tuberculin skin testing,and some vaccinations.

PHARMACOLOGY. 877

Intramuscular Subcutaneous Intravenous Intradermal

gO-degreeangle

10- to 15-degree angle

EpidermisDermisSubcutaneoustissueMuscle

Intramuscular

(1M)

Subcutaneous

(SC)

Intravenous

(IV)

Intradermal(10)

Figure 22-7 Parenteralmedications

intramuscular

(in-trah-MUSS-kyoo-lar)intra- = within

mU5culfo = muscle-ar = pertaining to

The medication is injected directLyinto the muscle.

IntramuscuLar injections are used for administering antibiotics, medica-tions that might be irritating to the layers of the skin, and medicationsthat require dosages larger than the amount allowed for a subcutaneousinjection.

intravenous

(in-trah-VEE-nus)intra- = within

venjo = vein-OU5= pertaining to

The medication is injected directLy into the vein, entering thebLoodstream immediateLy.

Intravenous injections are used when medication is needed quickly, andfor administering medication over a period of time, by adding the med-ication to a bag of intravenous fluids (a process known as infusion).

-"-----------

subcutaneous

(5ub-kyoo- TAY-nee-us)

5ub- = under, below

cutanejo = skin-OU5= pertaining to

The medication is injected into the subcutaneous Layer,or fatty tis-sue, of the skin.

Subcutaneous injections are used for administering insulin, hormones,and local anesthetics.

Drug ClassificationDrugs are classified, or categorized, according to their primary ormain effect(s) in the body. Table 22-2 lists most of the major classifi-cations of drugs, along with a basic description of each category anda common example of a medicine from each classification. Thegeneric name is written in lowercase letters and the brand namebegins with a capital letter.

878 . CHAPTER22

Table 22-2 MajorDrugClassifications

DRUGCLASSIFICATION

analgesic(an-al-JEE-sik)

an- = withoutaLgesjo =

= pertaining

anesthetic

(an-ess-THET-ik)an- = withoutesthetjo = feeling nervous

sensation orsense ofperception

-ic = pertaining to

antiarrhythmic(an-tee-ah-RITH-mik)

anti- = againstarrhythmjo =-ic = pertaining

antibiotic

(anti-infective)(an-ti h-BYE-ot-ik)

anti- = againstbijo = life-tic = pertaining to

anticoagulant(an-tih-koh-AG-yoo-lant)

anti- = againstcoaguLjo = clotting

anticonvulsant

(an- ti h-kon-VULL-sant)

antidepressant(an-ti h-dee-PRESS-ant)

antidiabetic

(an-tih-dye-ah-BET-ik)

antidiarrheal

(an-tih-dye-ah-REE-ul)

GENERAL-PURPOSE DEFINITION

Helps control the blood sugar level

treats diarrhea

COMMON EXAMPLE- -

phenoxymethyl-penicillin sodium(Pen-Vee-K, Penicillin VK,Veetids, V-Cillin K)trimethoprim and sulfameth-oxazole (Bactrim, Bactrim OS)

heparin calcium (Calcilean)warfarin sodium (Coumadin)

phenobarbital sodium(Luminal Sodium)diazepam (Valium)

hydrochloride

chlorpropamide (Oiabenese)tolazamide (Tolinase)insulin

diphenoxylate-atropi nesulfate (Lomotil)loperamide hydrochloride(Imodium)

antidiuretic

(an-tih-dye-yoo-REH-tic)

antiemetic

(an-tih-ee-MET -ik)

antifungal(an-tih-FUNG-gal)

anti- = againstfungjo = fungus-al = pertaining to

antihistamine(an-tih-HISS-tah-meen)

antihypertensive(an-tih-high-per-TEN-siv)

anti- = againsthyper- = excessive

anti-infective (antibiotic)(an-tih-in-FEK-tiv)

anti-inflammatory(an- tih- in-FLAM-ah-toh -ree)

antineoplastic(an-ti h-nee-oh-PLASS- tik)

= againstnejoplasjo formation-tic = pertaining to

antitussive

(an-tih- TUSS-iv)

antiulcer agent(an-tih-ULL-ser)

antiviral agent(an-tih-VYE-ral)

-~-~~"-

ed in allergic

Treats and prevents peptic ulcer andgastric hypersecretion

as

PHARMACOLOGY. 879

ine hydrochloride

maleate

Polymox)(Vibramycin)

nabumetone (Relafen)naproxen sodium (Anaprox,Aleve)

fluorouracil (Adrucil)methotrexate (RheumatrexDose Pack)

hydrobromideDM,RobitussinVick's Formula 44,

44 Pediatric

hydrochloride

Decongestant,PE, Sudafed

ranitidine hydrochloride (Zantac)nizatidine (Axid)

(Zovirax)(Vira-A)

880 . CHAPTER22

beta blocker(BAY-tahblock-er)

bronchodilator(brong-ko h-DYE-lay-tor)

bronch/o = bronchus;airway

(KAL-see-umCHAN-ellBLOCK-er)

diuretic

(dye-yoor-RET -ik)

hormone

(HOR-mohn)

hypnotic(hip-NOT-ik)

hypno- = sleep-tic = pertaining to

immunosuppressant(im-yoo- no h-suh-PRESS-ant)

immun/o = immunity

laxative(LACK-sah-tiv)

lipid-lowering agent(LIP-id)

liP/o = fat

sedative

(SED-ah-tiv)

(SKELL-eh-tal musclerih-LAK-sant)

skeletjo = skeleton-al = pertaining tomuscul!o = muscle-e = nounending

vitamin(VIGH-tah-min)

Prevents and treats vitamin deficiencies

and used as dietary supplement

(Premarin)

(Sandimmune)(Imuran)

docusate calcium (Surfak)bisacodyl (Oulcolax)psyllium hydrophilic muciloid(Metamucil)

niacin (Nicobid)lovastatin (Mevacor)

phenobarbital (Nembutal)diazepam (Valium)flurazepam hydrochloride(Dalmane)

dantrolene sodium (Dantrium)carisoprodol (Soma)cyclobenzaprine- hydrochloride(Flexiril)

VitaminsA, 0, E, etc.ascorbic acid (vitamin C)cyanocobalamin (vitamin 812)

880 . CHAPTER22

beta blocker

(BAY-tahblock-er)

bronchodilator

(brong-koh-DYE-lay-to r)bronch/o = bronchus;

airway

(KAL-see-umCHAN-ellBLOCK-er)

diuretic(dye-yoor-RET-ik)

hormone

(HOR-mohn)

hypnotic(hip-NOT-ik)

hypno- = sleep-tic = pertaining to

immunosuppressant(im-yoo-noh-suh-PRESS-ant)

immun/o= immunity

laxative

(LACK-sah-tiv)

lipid-lowering agent(LIP-id)

lip/o = fat

sedative

(SED-ah-tiv)

(SKELL-eh-tal musclerih-LAK-sant)

skelet/o = skeleton-al = pertaining tomuscul/o= muscle-e = noun ending

vitamin(VIGH-tah-min)

Relieves

Prevents and treats vitamin deficiencies

and used as dietary supplement

e,

(Vascor)

(Premarin)

(Sandimmune)(Imuran)

docusate calcium (Surfak)bisacodyl (Oulcolax)psyllium hydrophilic muciloid(Metamucil)

niacin (Nicobid)lovastatin (Mevacor)

phenobarbital (Nembutal)diazepam (Valium)flurazepam hydrochloride(Oalmane)

dantrolene sodium (Oantrium)carisoprodol (Soma)cycLobenzaprine- hydrochloride(FLexiril)

Vitamins A, 0, E, etc.

ascorbic acid (vitamin C)cyanocobalamin (vitamin B12)

PHARMACOLOGY. 881

Common Charting AbbreviationsMedical abbreviations are a form of shorthand that serve as a universal

language for medical professionals to provide specific information and/ororders in an abbreviated format. These abbreviations may be used on adaily basis by those involved in all aspects of health care. It is essential thathealth care professionals commit these abbreviations to memory to trans-mit and receiveclear and concise meanings. Some of the more commonlyused abbreviations that relate to pharmacology and are used for chartingare listed below.As you continue your studies in pharmacology and otheraspects of the medical field, your list of abbreviations will expand.

ABBREVIATION MEANING ABBREVIATION MEANING

aa of each h,hr hour

a.c. beforemeals h.s. hour of sleep

ad lib. as desired H2O water

AM mormng

I:intradermal

AQ, aq water intramuscular

b.i.d. twice a day

I inj.

injection

C Celsius (Centigrade) I.U. International Units

C with IV intravenous

cap(s) capsule, capsules kg kilogram

cc cubic centimeter LorI liter

em centimeter Ib pound

dc, D/C discontinue mg milligram

DEA Drug Enforcement Administration mEq milliequivalent

disp dispense mL or mI milliliter

dr dram mInIm

DS double strength n.p.o., NPO nothing by mouth

elix elixir O2 oxygen

F Fahrenheit O.D. right eye

FDA Food and Drug Administration oint., ung ointment

FDCA Food, Drug, and Cosmetic Act O.S. left eye

gal gallon OTC over the counter (drugs)

Gm., g, gm gram O.U. both eyes

gr grain oz ounce

gtt drops p after

882 . CHAPTER22

p.c. after meals

Physicians' Desk Reference sig

sol

PDR

PM afternoon

p.o. by mouth (per os)

p.r.n. asneeded

pt pint

q. every

q.a.m. everymormng

q.d.

q.h.

everyday

every hour

every2 hours,every3hours. . . .

tinct.

q.2 h.. q.3 h... . . .

q.h.s.q.i.d.

se.subq.sub-Q

sos

ss

stat.

supp.

T. Tbsp.

t.tsp.

tab.

t.i.d.

four times a day

at bedtime (every hour of sleep)

TO

q.o.d. every other day

quantity sufficientq.s.

qt

R

quart

rectal

take; treatment; prescriptionx

Rx

s without

'"

TERM

U

ung. oint.

USP/NF

VO

Written and AudioTerminology Review

subcutaneous

write on label (let it be labeled)

solution

if necessary

one-half

immediately

suppository

tablespoon

teaspoon

tablet

three times a day

tincture

telephone order

unit

ointment

United States Pharmacopeia/

National Formulary

verbal order

times, multiplied by

Review each of the following terms from this chapter. Study the spelling ofeach term and write the definition in the space provided. If you have the

Audio CD available, listen to each term, pronounce it, and check the box

once you are comfortable saying the word. Check definitions by looking

the term up in the glossary/index.

PRONUNCIATION DEFINITION

adverse reaction

analgesic

anaphylactic shock

anesthesia

anesthetic

D AD-vers reaction

D an-al-JEE-sik

D an-ah-fih-LAK-tic SHOCK

D an-ess- THEEZ-ee-ah

D an-ess-THET-ik

antiarrhythmic

antibiotic

anticoagulant

anticonvulsant

antidepressant

antidiabetic

antidiarrheal

antiemetic

antifungal

antihistamine

antihypertensive

anti-infective

anti-inflammatory

antineoplastic

antitussive

antiulcer

antiviral

beta blocker

bronchodilator

buccal medication

calcium channel blocker

chemical name

chemotherapy

contraindication

cumulation

cyanosis

diuretic

generic

hormone

Hospital Formulary

hypnotic

D an-tee-ah-RITH-mik

D an-tye-BYE-ot-ik

D an-tih-koh-AG-yoo-lant

D an-tih-kon-VULL-sant

D an-tih-dee-PRESS-ant

D an-tih-dye-ah-BET-ik

D an-tih-dye-ah-REE-al

D an-tih-ee-MET-ik

D an-tih-FUNG-gal

D an-tih-HISS-tah-meen

D an-tih-high-per- TEN-siv

D an-tih-in-FEK-tiv

D an-tih-in-FLAM-ah-toh-ree

D an-tih-nee-oh-PLASS-tik

D an-tih- TUSS-iv

D an-tih-ULL-ser

D an-tih-VYE-ral

D BAY-tah blocker

D brong-koh-DYE-lay-tor

D BUCK-al med-ih-KAY-shun

D KAL-see-um CHAN-ell

BLOCK-er

D KEM-ih-cal name

D kee-moh-THAIR-ah-pee

D kon-trah-in-dih-KAY-shun

D KYOO-mew-lay-shun

D sigh-ah-NOH-sis

D dye-yoor-RET-ik

D jeh-NAIR-ik

D HOR-mohn

D hospital FORM-you-lair-ee

D hip-NOT-ik---J

PHARMACOLOGY. 883

884 . CHAPTER22

hypoglossal

hypotension

idiosyncrasy

immunosuppressant

inhalation

intradermal

intramuscular

intravenous

laxative

lipid-lowering agent

oral

parenteral

pharmacist

pharmacodynamics

pharmacology

pharmacopeia

pharmacy

potency

potentiation

rectal

sedative

skeletal muscle relaxant

subcutaneous

sublingual

subungual

systemic

therapeutic

tolerance

topical

toxicology

vaginal

vitamin

D high-poh-GLOSS-al

D high-poh- TEN-shun

D id-ee-oh-SIN-krah-see

D im-yoo-noh-suh-PRESS-ant

D in-hah-LAY-shun

D in-trah-der-mal

D in~trah-MUSS-kyoo-lar

D in-trah-VEE-nus

D LACK-sah-tiv

D LlP-id lowering agent

D OR-al

D par-EN-ter-al

D FAR-mah-sist

D far-mah-koh-dye-NAM-iks

D far-mah-KALL-oh-jee

D far-mah-koh-PEE-ah

D FAR-mah-see

D POH-ten-see

D poh-ten-she-AY-shun

D REK-tal

D SED-ah-tiv

D SKELL-eh-talmusclerih-LAK-sant

D sub-kyoo-TAY-nee-us

D sub-LlNG-gwal

D sub-UNG-gwal

D sis-TEM-ik

D thair-ah-PEW-tik

D TAHL-er-ans

D TOP-ih-kal

D tocks-ih-KAHL-oh-jee

D VAJ-in-al

D VIGH-tah-min