Substance Abuse and Dependence

Psychiatry departmentBeni Suef University

Substance Abuse and Dependence

Important Definitions• Tolerance• Dependence• Addiction• Compulsive substance taking behavior• Withdrawal • Craving• Substance Abuse• Gateway Substances

Tolerance

• 1. Previous exposure to a drug or to a similar one• 2. Quantitative response characterized by either: a. A usual dose no longer evokes its desired

effect. b. A larger dose than the previous one must

be used to produce the same effect.

Dependence:

• This is an adaptive psychological, physiological and biochemical state caused by the repeated exposure to a drug.

• Continued use of the drug becomes necessary for the well-being of the organism.

• Sometimes the word "dependence" is used as a synonym of addiction.

Withdrawal

* Withdrawal syndrome: psychological or physiological symptoms may occur.

* A closely related substance is taken to relieve or avoid withdrawal symptoms.

Compulsive substance taking behavior:

* The substance is taken in larger amounts or over a longer period than intended.

* Unsuccessful efforts to cut down or control substance use.

* A great deal of time is spent in obtaining, using and recovery from substance effects.

* Social, occupational or recreational activities are given up or reduced.

* Continuing despite physical or psychological problems.

Craving:

• it is a strong subjective drive to use the substance. It is likely to be experienced by most (if not all) individuals with substance dependence.

Substance Abuse:

• It is repetitive use of substances resulting in recurrent and significant adverse consequences, e.g.

• * Failure to fulfill major role obligations at work, school or home.

• * Recurrent substance use in situations in which it is physically hazardous (e.g. driving an automobile).

• * Recurrent substance related legal problems.

Gateway Substances

• These are addictive substances their frequent use has been directly related to subsequent abuse and dependence of other more dangerous substances, such as Heroin and Cocaine.

• They include: 1. Tobacco 2. Cannabinoids (Hashish, Marijuana, Bango)

• They are the best predictor of other drug use during adolescence.

Addiction:

• The diagnosis of addiction implies the use of a drug with the following clinical criteria:

* The use of the drug is not upon medical indication

* Tolerance * Withdrawal

Types of Drugs of Abuse andDependence

• Most of substances known to be amenable for abuse and dependence (Addiction) can be grouped into the following classes:

1. Alcohol.2. Sedatives, hypnotics or anxiolytics.3. Cannabinoids [e.g. Bango - Hashish - Marijuana].4. Opioids [e.g. Heroin, Opium, Morphine, Codeine

and Codeine-containing cough sedatives].5. Cocaine.

Types of Drugs of Abuse andDependence

6. Amphetamines and other stimulants.7. Tobacco.8. Caffeine.9. Hallucinogens [e.g. LSD, Anticholinergics, Mescaline ...]10. Phencyclidine [e.g. Ketamine]11. Volatile solvents.

• N.B. Poly-substance abuse and dependence is common.

Substances may be mixed with others.

(1) Nicotine

• Nicotine, in mild to moderate doses, is a central nervous system stimulant.

• It enhances central cholinergic receptors (activated by acetyl choline).

• The dependence-producing effects of nicotine appear to be modulated by dopamine (nicotinic-cholinergic receptors lie on dopamine neurons, nicotine increases dopamine).

(1) Nicotine

• Nicotine also increases nor epinephrine, epinephrine, and serotonin and these increases may modulate some of the reinforcing effects from cigarettes.

• In large toxic doses, it exerts an inhibitory effect on peripheral cholinergic receptors.

Nicotine Withdrawal (Nicotine Abstinence Syndrome)

* Subjective symptoms:o Dysphoria or depressed mood.o Irritability.o Anxiety.o Decreased concentration.o Restlessness, impatience, confusion then rapidly appears.o Desire for nicotine.

* Objective symptoms (signs):o Decreased heart rate.o Insomnia.o Increased reaction time (reaction is slowed down).

Nicotine Toxicity:In low doses:

• signs and symptoms of nicotine toxicity include:* Pallor * Nausea & vomiting* Weakness * Dizziness * Salivation * Tremors * Abdominal pains & diarrhea* Cold sweats * Headache * Tachycardia * Increased blood pressure.

Nicotine Toxicity:At higher doses:

• * Seizures• * Hypotension• * Respiratory arrest can develop

Hazards of smoking

• Death is the primary adverse effect of cigarette smoking.

• Causes of death include:* Chronic bronchitis.* Emphysema.* Bronchogenic cancer.* Cerebrovascular disease.* Cardiovascular disease.

Hazards of smoking

• In pregnant women, nicotine crosses the placenta freely and is in the amniotic fluid and umbilical cord blood of neonates.

• Sustained exposure of the fetus causes:*Slow growth in utero and lower than average

birth weights.*Increased incidences of newborns with

persistent pulmonary hypertension.

Cannabinoids

Cannabinoids

• The psychoactive compound in cannabinoids is delta-9- tetrahydrocannabinol (THC).

• Cannabinoids are usually smoked, but may be taken orally and are sometimes mixed with tea or food.

• Common forms of Cannabinoids include Hashish. Marijuana, and Bango.

Cannabinoids

• THC is lipid soluble and rapidly absorbed after inhalation.

• It is redistributed from blood into other tissues.

• It is then released from its adipose tissue stores into the blood stream. This explains the prolonged effects of THC after acute intake.

http://upload.wikimedia.org/wikipedia/commons/e/ef/Bodily_effects_of_cannabis.svg

Effect of cannabinoids

• Cannabinoids exert many of their actions by influencing several neurotransmitter systems. These include acetylcholine, dopamine, gamma-amino-butyric acid (GABA), histamine, serotonin, norepinephrine, opioid peptides, and prostaglandins.

cannabis intoxication

• in the form of impaired motor coordination, euphoria, anxiety, sensation of slowed time, impaired judgment and social withdrawal.

Cannabis withdrawal

• have been described in association with the use of high doses in the form of:

* Irritable or anxious mood* Tremor* Perspiration* Nausea* Sleep disturbances

Hazards of cannabinoids• Chronic cannabinoids use is associated with poor social

and vocational functioning due to the development of Amotivational Syndrome.

• A number of psychiatric disorders such as bipolar mood disorder, anxiety, depersonalization, and dissociative episodes are reported as a consequence of cannabinoid abuse.

• Affective disorders and paranoid symptoms may be exacerbated after cannabinoid abuse

Opioids

• Opioids are highly addicting. • Forms of Opioids include opium, morphine,

heroin, codeine and some analgesic opiate derivatives.

Acute effects of Opioids• 1. Central nervous system effects: Opioids are

central nervous system suppressants (endogenous opioid receptors).

Their effects include:* Analgesia

* Mood changes* "Mental clouding",

* Sedation* Central nausea and vomiting

• 2. Gastrointestinal effects:• 3. Pupillary constriction• 4. Respiratory depression

Over dose of opiatesSevere intoxication is diagnosed by the triad of:• 1- Coma• 2- Pinpoint pupils• 3- Respiratory depression. • It is a medical emergency that requires

immediate attention.

Opioids Withdrawal Syndrome

• Time of onset differs according to the half-life of the drug used: e.g. 4-6 hours after the last use of heroin but up to 36 hours after the last use of methadone.

• Severity varies with the dose and duration of drug use.

• Early findings may include tachycardia, hypertension, pupillary dilatation, and diffuse musculo-skeletal pains

Opioids Withdrawal Syndrome

• Central nervous system symptoms include restlessness, irritability and insomnia

• Gastrointestinal symptoms are anorexia, vomiting, abdominal colics, and diarrhea

• Cutaneous and mucocutaneous symptoms include lacrimation, rhinorrhea and piloerection , also known as "gooseflesh"

• Opioids Craving

Alcohol

• 90% of USA population are using alcohol, whereas only 12% or 18% have abuse or dependence problem, respectively.

Effect of alcohol on the brain

• * Alcohol is a CNS suppressant. • It exerts this suppressant effect in a

descending manner, where higher cortical centers are inhibited first, resulting in euphoria and then disinhibition.

• In larger doses, lower vital centers are inhibited, leading to hypotension and respiratory depression.

Effect of alcohol on neurotransmitters

• * It is found that ion channel activities associated with acetyl choline, serotonin and GABA receptors are enhanced by alcohol.

• Ion channel activities associated with glutamate receptors are inhibited.

• * Death is due to central respiratory depression or inhalation of vomitus

Alcohol-Related Disorders

* Alcohol abuse and dependence.* Alcohol withdrawal* Alcohol induced dementia.* Alcohol induced amnestic disorders.*Alcohol induced psychotic disorders* Alcohol related mood disorder.

Alcohol withdrawal• The classic signs of alcohol withdrawal are due

to sympathetic over activity and tendency to develop epileptic convulsions.

• Symptoms include tremulousness, sweating, restlessness and even excitement.

• They may include psychotic symptoms (such as delusions and hallucinations).

• Seizures and symptoms of delirium tremens may eventually develop.

• Treatment is Benzodiazepines.

Fetal alcohol syndrome

• It occurs when fetuses are exposed in utero to alcohol by their mothers' drinking alcohol.

• This syndrome is the leading cause of mental retardation in the United States.

• Women with alcohol related disorders have a 35 percent risk of having a child with deficits.

Hallucinogens

• Agents that induce a state of marked perceptual alterations.

• They are CNS stimulants. • Examples are:• lysergic acid diethylamide (LSD) and

amphetamines. • They have both an antagonist and an agonist

effect on serotonergic systems.

lysergic acid diethylamide (LSD)

• LSD is synthetic derivative of ergot fungus. • It is extremely potent and is effective in

extremely low doses.• It is ingested orally or through other mucous

membranes (sublingual, orally or corneal). • Tolerance quickly develops, leading to ingestion

of larger doses or increased frequency of use.• It is not highly addicting,

Hazards of hallucinogen use

1. A drug precipitated psychosis may continue following the cessation of hallucinogen use.

2. Flashbacks are brief spontaneous recurrences of perceptual changes, such as experienced while using hallucinogens.

They have been reported days, months or years after drug use.

Cocaine

• Cocaine is one of the most addictive of commonly abused substances and one of the most dangerous.

• Cocaine, variously referred to as crack, snow, cock, girl and lady,

• It is a white powder that is inhaled, smoked or injected.

Effect of cocaine on CNS

• Cocaine is a psychoactive stimulant. • Its primary pharmacologic action is related to its

competitive blockade of dopamine reuptake by dopamine transporters.

• This leads to marked elevation of dopamine in synaptic clefts.

• Cocaine has powerful addictive qualities. • psychological dependence on cocaine can

develop after a single use.

Withdrawal symptoms of cocaine

• Withdrawal symptoms are mild compared to those of opioids.

• They include depressed mood, dysphoria, fatigue, hypersomnolence.

• Suicidal ideations may occur. • Symptoms persist for a few days up to one

week. • Craving is very strong.

Over dose of cocaine

• Intoxication by high doses is associated with delirium, seizures, cerebrovascular diseases and myocardial infarction which may lead to death.

Psychiatric disorders with cocaine abuse

They include:• psychotic disorders,• mood disorders, • anxiety disorders, • sexual dysfunction and• sleep disorders.

Benzodiazepines (BDZ)

• Benzodiazepines are psychoactive depressant drugs that are used to control anxiety and epilepsy and in induction of anesthesia.

• Tolerance to benzodiazepines is common. • Benzodiazepines are widely used in

combination with heroin, cocaine, alcohol and stimulants.

Intoxication of BDZ

• includes somnolence and behavioral disinhibition.

• In higher doses, they cause hypotension and central respiratory depression, particularly if taken with another depressant drug (e.g., alcohol).

Withdrawal of BDZ• symptoms include rebound anxiety, restlessness,

agitation, hypertension, and tachycardia. • Epileptic seizure is a serious emergency and may

be fatal. • Hospitalization and gradual withdrawal of

benzodiazepines are the main lines of treatment of benzodiazepine addiction.

• Prevention of seizures by antiepileptics may be needed.

Management of Substance Abuse/Dependence

• Two major goals: • the first is abstinence from the

substance; • the second is physical, psychiatric, and

psychosocial well-being of the patient.

Management of Substance Abuse/Dependence

• * Inpatient or outpatient settings.• * Detoxification, • * Rehabilitation.• * Throughout treatment, individual, family,

and group therapies (alcoholic & narcotic anonymous) can be effective.

• * Any underling psychiatric disorder should be diagnosed and appropriately treated.

Rehabilitation centre

Pharmacological Treatment of Substance Abuse

• * Because substance abuse/dependence is in part a neuropharmacological phenomenon, there is at present an aggressive search for agents that may:

o decrease the reinforcing properties of substances (block the drug euphoric effect)

o decrease craving associated with substanceso function as replacements for the drug of

abuse

Pharmacological Treatment of Substance Abuse

• * Naltrexone (an opiate receptor blocking agent) decreases alcohol consumption and relapse in alcoholic patients, also in opiate abuse.

• * Nicotine replacement using nicotine gum, patch, spray and inhalation have been used with successful results in nicotine dependence.

• * Methadone - an opiate receptor agonist - proved to be highly effective in abstinence from opiate use.

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