A drug is defined by WHO as any substance that when taken into the living organism

may modify one or more of its functions.

• Drugs of abuse are generally defined as substances that when taken alter mood, cognition

(thoughts) and behavior.

• There are four important patterns of drug use disorders, which may overlap with each

other

- Acute Intoxication

This is a transient condition following administration of a drug resulting in

psycho-physiological disturbances

Withdrawal Syndrome

Develops on total or partial withdrawal of drugs, usually after repeated and/ or

high dose use

The withdrawal symptoms last after a few hours to few days

-Dependence/Tolerance

Characterized by tolerance i.e. craving needs for higher dose of drug to get the

same benefit as previous

Known pharmacologic effect of many medications including opiates,

benzodiazepines

This may not mean addiction but need to carefully assess the situation

-Abuse/Addiction

Continue use despite awareness of harmful medical/ social effects

Addiction craving need for a drug that one cannot do without it.

Common Drugs of Abuse Found in our Society

• Alcohol

• Cannabis

• Heroin

• Cocaine

• Sedatives and hypnotics e.g. barbiturates, benzodiazepines

• Inhalants e.g. volatile solvents

• Opiates

Alcohol Use Disorders

• Excessive consumption of alcohol

• Alcohol abuse refers to excessive use of alcohol causing mental, physical or social harm

to the individual.

• Alcohol Dependence describes ‘a pattern of repeated self-administration of alcohol that

usually results in tolerance, withdrawal and compulsive alcohol-taking behavior. The

essential element of which is the continued use of the substance (alcohol) despite of its

related problems.

Clinical Features of Alcohol Intoxication

• Psychomotor impairment

• Exaggerated emotional responses

• Impaired judgment

• Ataxia

• Slurred speech

• Decreased concentration

• Labile mood

Alcohol Withdrawal Symptoms

• Usually occurs 6–24 hours after last drink and the symptoms are progressive

• Tremor

• Anxiety and agitation

• Sweating

• Nausea and vomiting

• Headache

• Sensory disturbances e.g. hallucinations or illusions

• Convulsions (seizures)

• Delirium tremens (DTs)

-Clouding of consciousness with disorientation in time and place

-Tremors

-Visual hallucination

-Psychomotor agitation and ataxia

-Insomnia

-Dehydration

• Alcohol withdrawal seizures may be of tonic clonic type and is of single episode most

likely. Sometimes status epilepticus may be precipitated. Thereafter, delirium tremens

may follow.

• Alcohol withdrawal is a medical emergency and should prompt referral to hospital for

further management.

Management of Alcohol Use Disorder

Investigations

• Hemoglobin

• ESR

• Widal test

• Mean corpuscular volume (MCV)

• Gamma glutamyl transferase (GGT)

• Liver function test

• Blood slide for malaria parasites

• Urinalysis

• Stool for oval

• HIV Test

Treatment

• The goal of treatment is to prevent medical and social adverse effects during period of

intoxication.

• The treatment may be non-pharmacological and pharmacological. Non-pharmacological

measure includes

-Providing safe environment and reassurance

-General medical support with iv fluids and respiratory assistance

• Pharmacologically, no antagonist (antidote) available

Treatment of Alcohol Withdrawal

• Stop alcohol use then manage withdrawal symptomatically by using

-Diazepam 30-40mg per day in divided doses (i.e. 10 mg three times daily) reducing to

-by the end of day 5. This needs to be done in a controlled environment such as the

hospital and not as an outpatient therapy.

-Thiamine & multivitamins- because oral thiamine is poorly absorbed in patients with

a pattern of chronic alcohol consumption, high doses ideally parenterally 100 mg

intramuscularly should be considered in the first instance

-Thiamine ≥100 mg daily

-Antiemetic

-analgesia such as paracetamol

-Any electrolytes imbalance should be corrected

-Fluid balance needs to be maintained. Patient may need IV fluid hydration with

isotonic solution such as normal saline

• Behavioral therapy, psychotherapy and group therapy is adjuvant therapy and it is

conducted in a specialized psychiatric unit by clinical psychologist.

Treatment of Alcohol Dependence

• Pre-Referral Treatment

-Treat alcohol withdrawal as explained above then refer the patient to a specialized

hospital

Cannabis Use Disorders

• Cannabis is derived from herb plant called Cannabis sativa

• Cannibis is a drug widely used in some subcultures and is thought to cause physical

dependence.

• When smoked, the drug seems to exaggerate the pre-existing mood, be it depression,

euphoria or anxiety.

• There is no definite withdrawal syndrome.

• While cannabis use can result be characterized by acute anxiety, depression or

hallucinations, there is no convincing data that a persisting psychosis can result.

• However, there is evidence that cannabis smoking increases the risk of developing

schizophrenia in individuals so predisposed, and may aggravate the condition once it has

manifested it.

Clinical Effects of Cannabis Use

• Acute Effects of cannabis include

-Pain perception is reduced

-Anti-nauseate and anti-emetic effects

-Increased appetite

-Anticonvulsant effects

• CNS depressant effects of cannabis include

-Drowsiness

-Reduced alertness

-impairment of short term memory,

-Slowed reactions

-Reduced accuracy of psychomotor task performance

-Reduced motor coordination and muscle tone

-Dysphoria, increased anxiety and panic reactions especially in inexperienced users

-Sensory distortions, hallucinations

• Cardiovascular effects

-Tachycardia

-High Cardiac Output

-High Myocardial Oxygen need

• Effects of cannabis in the respiratory system include

-bronchodilation leading to reduced airway resistance in acute phase

-Bronchial irritation due to particulate fraction of cannabis smoke in chronic phase

-Cannabis smoke similar to tobacco smoke

• In the eye, cannabis leads to reduced intraocular (IOP) at doses that produce CNS effects

• Effects of cannabis in the immune system is unclear but there are chronic inflammatory

chest disease as well as precancerous changes

Management of Cannabis Use Disorder

Investigations

• Urine test for cannabinoid done at government chemistry laboratory

Treatment

• No specific pharmacotherapies are available yet for managing cannabis withdrawal or

relapse

• Motivational interviewing technique available at specialized hospital

Other Drugs of Abuse

• There are many other drugs that are used for abuse, these drugs include

-Cocaine

-Heroine

-Barbiturates

-benzodiazepines

-Volatile substances

Other Drugs of Abuse

Heroin Abuse

• Semi synthetic

• Heroin is prepared by reacting morphine with acetic anhydride or acetyl chloride

Uses

• By injection

• By sniffed/snorted, smoked

Heroin Overdose

• Clinical trial of respiratory depression, CNS depression and miosis

• Drowsiness, ‘nodding off’

• Slurred, drawling speech

• Pinpoint pupils

• Ataxia, emotional liability

• Respiratory rate is less than12 per minute

• Bradycardia, hypotension

• May progress to coma

Short Term Effects

• Soon after injection or inhalation heroin crosses the blood brain barrier

• In the brain heroin is converted to morphine and binds to opioid receptors (mu, kappa and

delta)

• Users report feeling a ‘rush’: accompanied by warm flushing of the skin, dry mouth and

heavy feeling in the extremities

• May also experience nausea, vomiting and severe itching

• Cardiac function slows

• Breathing severely slowed which may progress to death

Long Term Effects

• Tolerance and physical dependence

• Tolerance to analgesic effects develops slowly but tolerance to psychoactive effects

develops rapidly

• Addiction

• Medical complications

• Viral infections like hepatitis B, hepatitis C and HIV

• Scarred/collapsed veins

• Bacterial infections such as abscesses and endocarditis

Symptoms of Heroin Withdrawal

• Intense anxiety and dysphoria

• Craving for heroin

• Insomnia, fatigue

• Myalgias, chills

• Nausea, abdominal cramps, diarrhea

Treatment of Heroin Overdose/Intoxication

• Naloxone (opioid antagonist)

• Duration of action of naloxone is much shorter than that of opioid agonists

• Its peak effects is 5-15minutes and duration of action is only 60 minutes

• Patients who respond to naloxone must not be discharged until opioid effects have

completely worn off

Treatment of Withdrawal

Pharmacological Treatment

• Detoxification

• Usually an inpatient admission with methadone as a substitute which is prescribed in

special psychiatric hospital

Symptomatic Treatment

• Such as loperamide 2mg bid for treating withdrawal diarrhea

• Diazepam short course for treating withdrawal insomnia, but be cautious using

benzodiazepines in this situation as they may worsen the condition.

• Pharmacological treatment Options work best when combined with counseling and

structured relapse prevention programs

Barbiturates Abuse

Symptoms of Barbiturate Intoxication

• Sluggishness

• In coordination

• Difficulty in thinking

• Slowness of speech

• Faulty judgment

• Drowsiness or coma

• Shallow breathing

• Staggering

Barbiturate Dependence

• Barbiturates are a type of depressant drug that causes relaxation and sleepiness

• In relatively low doses barbiturates and alcohol have very similar clinical syndromes of

intoxication

• Excessive and prolonged dosages of barbiturate drugs such as phenobarbital, may

produce the following chronic symptoms

-Memory loss, irritability, changes in alertness, and decreased interpersonal

functioning

-Barbiturates may also cause an acute overdose syndrome which is life-threatening

Treatment of Barbiturate Intoxication

• There is no direct antidote to barbiturates or alcohol overdose

• In such overdoses respiration must be maintained by artificial means until the drugs are

removed from the body.

• Ensure breathing and circulation as well.

• Ensure adequate fluid hydration

Treatment of Barbiturate Dependence

• Is done by gradual withdrawal in stepwise manner such as reduction of 10% of the dose

every day.

• After detoxification phase follow up supportive counselling is essential to prevent

relapses.

• Benzodiazepines Abuse

• Is class of psychoactive drugs typically prescribed to treat conditions such as anxiety and

insomnia.

• They have a tranquilizing effect on the central nervous system.

Benzodiazepine Dependence

• Especially when they exhibit at least 3 of the following behaviours within a 12 month

period.

-Tolerance to the medication to the extent that the patient needs to take more to

achieve the same effects.

-Withdrawal symptoms when the medication is discontinued and taking other drugs to

relieve symptoms.

-taking higher and higher dosages against the doctor's prescription and when they

aren't needed.

-An inability to stop.

Treatment of Benzodiazepine Dependence

• As in barbiturate dependence

• True benzodiazepine withdrawal can be life threatening (similar to alcohol) and needs to

be treated in hospital with slow taper of benzodiazepine over several days

Volatile Substances Abuse

• Commonly referred to as inhalants, solvents or solvent based products

• 4 categories of inhalants

-solvents

-Aerosols

-Gases

-Nitrites

Clinical Features of Volatile Substance Abuse

• Red, watery eyes

• Sneezing & coughing (URTI-like symptoms)

• Chemical smell or odour on breath

• Glue, solvent, or paint stains on clothing, fingers, nose, or mouth

• Apparent intoxication/altered behaviour/risk taking

• Incoherence, confusion

• Poor coordination

• Excessive sweating

• Unusual spots, marks, rashes and sores around nose and mouth

• Excessive nasal secretions, constantly sniffing

Treatment of Volatile Intoxication

• Ensure fresh air and breathing

• Be calm and calming

• Persuade to cease sniffing if patient can communicate

• Take person to a safe environment

• Don’t attempt to counsel while intoxicated, drowsy or heavily intoxicated

• Consider the best environment for the individual and monitor physical and mental health

• Need to make patients aware that some side effects of these substances can cause

permanent changes.

Cocaine Abuse

• Cocaine is an alkaloid derived from the coca bush erythroxylum coca

• Cocaine is a central stimulant which inhibits the re-uptake of dopamine along with that of

nor-epinerphrine and serotonin

Clinical Features of Cocaine Use Disorder

• Pupillary dilatation

• Tachycardia

• Hypertension

• Nausea and vomiting

• Increased psychomotor activity

• Elation of mood

• Pressure of speech

• Impaired judgment with social or occupational dullness

• It can precipitate a myocardial infarction

Other Clinical Features

• Severe anxiety

• Paranoia (fear/obsession)

• Psychosis

• Irritability

• Confusion

• Desire to isolate

• Memory impairment

• Inability to concentrate

• Loss of control

• Aggressiveness

Complications of Chronic Cocaine Use

• Tactile hallucinations

• Cardiac arrhythmias

• Lung damage

• Foetal hypoxia

• Perforation of nasal septum

Cocaine Use Withdrawal Syndrome

• Withdrawal tends to peak 2–4 days following cessation of use

• Dysphoria rather than depression which may persist up to 10 weeks plus at least two of

the following

-Fatigue

-Insomnia/hypersomnia

-Psychomotor agitation

-Craving

-Increased appetite

-Vivid unpleasant dreams

Treatment of Cocaine Withdrawal

• To date, no effective pharmacotherapy for withdrawal management

• Prescribed medications

-Short-term use of benzodiazepines for

Anxiety

Agitation

Promotion of sleep

-Note: Benzodiazepines need to be used cautiously as they can cause delirium and

make things worse

• Psychotherapy

 

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