Substance Use Disorders Overview

Substance Use Disorders Overview

• Psychoactive drugs alter behavior, mood, thoughts, or consciousness. Examples include tobacco, alcohol, cannabis, and caffeine.
• Many of these drugs are used recreationally.
• The mechanism of action (MOA) describes how these drugs work, categorized as depressants, stimulants, or hallucinogens.
• Substance use disorder involves compulsive use or craving that interferes with daily functioning.
• Tolerance is the increased need for more of a drug over time.
• Withdrawal involves aversive symptoms when stopping a drug.
• Dependence is when the drug must be taken continuously to avoid withdrawal.
• Key signs of a substance use disorder include: taking larger amounts for longer periods than intended, strong urges to use, unsuccessful attempts to cut back, significant time spent obtaining/using/recovering, trouble with responsibilities, continued use despite relationship problems, giving up activities due to use, developing tolerance, experiencing withdrawal, and sustained use despite physical or psychological problems.
• Potential factors leading to substance use disorder include social pressure, curiosity, performance enhancement, emotional escape. Progression often follows a pattern: experimental, occasional, heavy use, then possible disorder.

Depressants

• Depressants reduce nervous system activity. Severe overuse can be fatal.
• Depressants are most associated with withdrawal, tolerance, and dependence. Common examples are alcohol, sedative-hypnotics, and anxiolytics.

Alcohol

• Alcohol is absorbed into the bloodstream and impacts the central nervous system. Initial stimulation can be followed by depressant effects; the liver metabolizes alcohol at about ¼ ounce per hour.
• Heavy alcohol use slows the central nervous system, decreasing control of bodily functions like breathing and gag reflex.
• Alcohol withdrawal can range from mild (sweating, nausea) to very serious (hallucinations, seizures, delirium tremens (DTs)).
• Alcohol use disorder (AUD) involves impaired control over drinking amounts and frequency; negative emotional states occur when not drinking.
• AUD is often called alcoholism and can pose health and safety risks. Binge drinking (5+ drinks within 2 hours for men; 4+ for women) is a common pattern.

AUD Criteria

• At least two of the following for at least 12 months: increased drinking, unsuccessful attempts to stop, significant time spent obtaining alcohol, craving alcohol, missed responsibilities, continued use despite problems, risky use, tolerance/withdrawal. AUD is categorized as mild, moderate, or severe.

AUD Risk Factors

• Regular drinking habits, early start, family history, depression, mental health concerns, trauma, bariatric surgery, and social/cultural factors.

Sedative-Hypnotics & Anxiolytics

• Sedatives (barbiturates) and sedative-hypnotics and Tranquilizers (benzodiazepines) are used for insomnia and similar conditions
• Both groups cause a calming effect, but benzodiazepines are safer than barbiturates.
• Use of both can be abused and produce withdrawal symptoms and impact GABA receptors.

Intoxication and Withdrawal (Sedative-Hypnotic-Anxiolytic-Related Disorders)

• Intoxication signs include reduced blood pressure/heart rate, slurred speech, lack of coordination, and impaired attention/memory.
• Withdrawal signs include agitation, anxiety, nausea, insomnia, and potentially seizures.

Stimulants

• Stimulants increase nervous system activity. Small doses can enhance alertness, but higher doses can lead to psychosis, convulsions, or death.
• Common stimulants include caffeine, nicotine, amphetamines, and cocaine.

Caffeine

• A recommended daily dose is 400mg.
• Caffeine stimulates the cerebral cortex, boosting energy and alertness.
• Caffeine effects can last up to 4 hours, and while moderate doses affect sleep, higher doses can cause anxiety and digestive problems. Reducing caffeine should occur slowly.

Tobacco Use Disorder

• Nicotine is a stimulant in tobacco that increases energy, pain tolerance, alertness, and reduces anxiety, hunger, and anger. It can damage lungs and cause medical conditions such as COPD.

Cocaine and Methamphetamine

• Cocaine is a powerful, natural stimulant that increases dopamine, leading to increased energy and euphoria. Long-term use can lead to depression, tremors, hallucinations, and convulsions.
• Methamphetamine is a highly addictive stimulant that increases dopamine as well. Long-term effects include severe itching, "meth mouth," and cognitive/emotional problems.

Opioids

• Opioids relieve pain and reduce nervous system activity, causing initial tingling and warmth. Examples include morphine, heroin, codeine, and methadone.
• Opioid intoxication involves nervous system suppression, loss of consciousness, seizures, coma, and potentially death.
• Opioid withdrawal increases pain sensitivity, causes cravings, nausea, sweating, and gastrointestinal distress.

Cannabis

• Cannabis sativa contains THC, a psychoactive substance whose effects can vary.
• Cannabis has aspects of stimulants, depressants, and hallucinogens. It is consumed orally or inhaled.
• Cannabis intoxication involves changes in mood, altered perceptions, and possible hallucinations, depending on the dosage.
• Cannabis withdrawal can include insomnia, restlessness, irritability, flu-like symptoms, and gastrointestinal problems.

Hallucinogens

• Hallucinogens or psychedelics distort conscious experiences. Examples include LSD (lysergic acid diethylamide) and PCP (phencyclidine).
• LSD ingestion can involve powdered or pill forms and causes unpredictable sensory effects and hallucinations.
• PCP use is typically via snorting, injecting, or smoking and produces feelings of power and body distortion, but high doses can cause flat mood, talkativeness, slow reaction, and muscle weakness.

Other Drugs of Abuse

• Inhalants (aerosol paints) absorbed rapidly into the bloodstream and cause damage to organs.
• Anabolic steroids are prescribed for medical reasons but can be misused for muscle-building.
• Dissociative anesthetics (e.g., ketamine) cause out-of-body experiences, sleepiness, reduced pain, and potentially unconsciousness.
• MDMA (ecstasy) induces euphoria, reduced anxiety and intimacy, but can cause increased tolerance.
• GHB is a depressant, used for anxiety and relaxation, but also impairs memory and can be used for sexual assault.

Behavioral Addiction: Gambling Disorder

• Gambling disorder involves problematic gambling, negatively impacting livelihoods and well-being. It often includes tolerance (needing increasing stakes for excitement) and behaviors like lying to conceal extent of gambling.

Models and Treatments of Substance Use Disorders

• Biological Models: Genetic factors and neurotransmitter systems are implicated, with reward circuits and dopamine significant. Detoxification is an initial step, followed by gradual reduction and, if necessary, relapse prevention medications.
• Cognitive-Behavioral Models: Operant conditioning and reinforcement play a role in disorder development. Treatments focus on modifying thoughts, feelings, and behaviors associated with substance use (e.g., aversion therapy, Acceptance and Commitment Therapy).
• Sociocultural Models: Sociocultural factors like cultural norms, peer influence, and societal attitudes towards substances affect substance use. Treatments often involve individuals and communities and include support groups.