Chapter 40

Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc.

Chapter 40

Drug Abuse IV: Major Drugs of Abuse Other Than Alcohol and

Nicotine

2Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc.

Drug Abuse IV: Major Drugs of Abuse

Heroin and other opioids General CNS depressants Psychostimulants Marijuana and related preparations Psychedelics 3,4-Methylenedioxymethamphetamine (MDMA,

Ecstasy) Phencyclidine Inhalants Anabolic steroids


Heroin, Oxycodone, and Other Opioids

Major drugs of abuse Most opioids are Schedule II Patterns of abuse Subjective and behavioral effects Preferred drugs and routes of administration


Heroin Patterns of use

Greatest use among 18- to 25-year-olds All segments of society First exposure usually social or for pain management

Subjective and behavioral effects Moments after IV injection, lower abdominal sensation that is

similar to sexual orgasm and lasts about 45 seconds Followed by euphoria Initial use causes nausea and vomiting

Preferred drugs and routes of administration Opioid of choice for street use High lipid solubility IV route preferred, but also smoking, nasal inhalation


Meperidine Nurses and physicians who abuse opioids

often select meperidine Highly effective in oral route (unlike injections,

leaves no sign) Minimal effect on smooth muscle: fewer problems

with constipation and urinary retention


Oxycodone Opioid similar to morphine

Intended as controlled-release drug (OxyContin) Abusers crush tablet Snort powder or dissolve in water for IV Entire dose absorbed immediately with high risk of

death Tolerance and physical dependence


Oxycodone Treatment of acute toxicity

Classic triad • Respiratory depression, coma, pinpoint pupils

Naloxone (Narcan) Nalmefene (Revex)


Tolerance and Physical Dependence

Tolerance Prolonged use Effects for which tolerance develops Effects for which tolerance does not develop

Cross-tolerance Physical dependence

Long-term use Abstinence syndrome Acute phase and second phase


Opioid Detoxification Detoxification

Methadone substitution • Long-acting oral opioid• Most commonly used agent• Approximately 10 days

Clonidine-assisted withdrawal Rapid and ultrarapid withdrawal


Drugs for Long-Term Opioid Addiction Management

Three groups of medications Opioid agonists, opioid agonist-antagonists, and

opioid antagonists Methadone

Maintenance and suppressive therapy Buprenorphine

Maintenance therapy and detox facilitation Naltrexone

Discourages renewed opioid abuse


Sequelae of Compulsive Opioid Use

Few direct detrimental effects Treatment programs vs. street drugs and

subculture Accidental overdose


General CNS Depressants Barbiturates, benzodiazepines, alcohol, and

other agents Benzodiazepines have unique properties


Barbiturates Depressant effects are dose-dependent

Mild sedation to sleep to coma and death Subjective effects similar to those of alcohol Agents with short to intermediate duration of

action have highest abuse incidence and are Schedule II Amobarbital, pentobarbital, and secobarbital


Benzodiazepines Tolerance Physical dependence and withdrawal

techniques Acute toxicity Flumazenil (Romazicon) Benzodiazepines (Schedule IV)

Much safer than barbiturates Overdose rare when taken alone and orally Risk increased with IV or with other depressants

Alcohol and miscellaneous CNS depressants Methaqualone (Quaalude)


Psychostimulants CNS stimulants (Schedule II) that have a high

potential for abuse Amphetamines Cocaine Related substances

Can stimulate the heart, blood vessels, and other structures under sympathetic control


Cocaine Extracted from leaves of coca plant CNS effect similar to that of amphetamines Two forms used by abusers

Cocaine “Crack”

Can produce local anesthesia, vasoconstriction, and cardiac stimulation


Cocaine Cocaine

Cocaine hydrochloride • White powder• Diluted for sale• Taken intranasally

Cocaine base: commonly called “crack”• Also called “crystals” or “rocks”• Heated for use• Taken by IV injection


Methamphetamines In abuse, usually taken orally, snorted,

smoked, or IV Also called “ice” or “crystal meth”

Form of dextroamphetamine Smoked, snorted, or inserted into rectum

Effects Arousal, euphoria, sense of increased physical

strength and mental capacity Hallucinations, psychotic state, sympathomimetic

actions


Methamphetamines Other adverse effects Tolerance, dependence, and withdrawal Treatment

Bupropion (Wellbutrin, Zyban) Modafinil (Provigil, Alertec)


Marijuana Cannabis sativa (hemp)

Marijuana and hashish are derivatives Common names: “grass,” “weed,” “pot”

Most commonly used illicit drug in the United States

95 million Americans have tried marijuana at least once


Marijuana Psychoactive substance

Delta-9-tetrahydrocannabinol (THC) Routes

Smoking• 60% of THC content absorbed, effects begin in minutes

and peak within 20–30 minutes Oral

• Majority of THC is inactivated by first-pass effect


Marijuana

Increased production of prostaglandin E2 Behaviors

• Euphoria• Sedation• Hallucinations

Therapeutic uses• Antiemetic• Appetite stimulant• Neuropathic pain


Marijuana Effects

Low to moderate dose High dose Long-term use


Marijuana Effects

Low to moderate dose High-dose Long-term use Schizophrenia

Cardiovascular Dose-related increase in heart rate

Respiratory Acute: bronchodilation Chronic: airway constriction


Marijuana Reproduction

Males and females affected Altered brain structure

Hippocampal volume left hemisphere Tolerance and dependence


Therapeutic Use Marijuana Approved uses for cannabinoids Unapproved uses for cannabinoids Medical research on marijuana Legal status of medical marijuana


Therapeutic Use Marijuana Comparison of marijuana with alcohol

Aggressive behavior is rare with marijuana use Loss of judgment is less with marijuana Increased appetite with marijuana: fewer problems

with nutritional deficiencies Marijuana produces increased toxic psychosis,

dissociative phenomena, and paranoia, more so than with alcohol


Psychedelics Lysergic acid diethylamide (LSD)

Acts on serotonin receptors of brain Routes: oral, IV, smoked Alters the following (as otherwise occurs only in

dreams):• Thinking• Feelings• Perception • Relationship to environment


Other Psychedelic Drugs Subjective and behavioral effects are similar

to those of LSD None approved for medical use Salvia Mescaline

From peyote cactus Psilocybin Psilocin Dimethyltryptamine


Dissociative Drugs Phencyclidine (PCP) and ketamine

Original use: surgical anesthetics Recreational use: distort sight and sound and

produce dissociation Act in the cerebral cortex and limbic system

PCP synthesized/manufactured easily by amateurs

Routes: oral, intranasal, IV, smoking Ketamine


Dissociative Drugs Phencyclidine (PCP)

Effects• Low to moderate doses, high doses

Toxicity Ketamine

Similar to PCP in structure, mechanism, and effects

Shorter duration of effects


Dextromethorphan OTC cough suppressant

Low dose for antitussive: no psychologic effects At doses 5–10 times higher, produces euphoria,

disorientation, paranoia, altered sense of time, and hallucinations

Also used in combination cold products Highly abused by adolescents and teenagers

OTC = over-the-counter.


3,4- Methylenedioxymethamphetamine Common names: MDMA, Ecstasy

Complex drug with stimulant and psychedelic properties

Structurally related to methamphetamine (stimulant) and mescaline (hallucinogen)• Low doses: mild LSD-like psychologic effects• Higher doses: amphetamine-like effects

Promotes release of neurotransmitters Usually taken orally; also snorted, injected, or

taken by rectal suppository


MDMA, Ecstasy Adverse effects

Can injure serotonergic neurons, stimulate the heart, and dangerously raise body temperature

Neurologic effects Seizures, spasmodic jerking, jaw clenching, teeth

grinding Confusion, anxiety, paranoia, panic


Inhalants Term can refer to many drugs; common

characteristic is administration by inhalation Anesthetics Volatile nitrites Organic solvents


Anabolic Steroids Androgens

Taken to enhance athletic performance Increase muscle mass and strength Massive doses that are often used have high risk

for adverse effects Most are classified as Schedule III drugs

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Chapter 40