Stimulant use disorder
From IDWiki
Background
- A substance use disorder that includes cocaine (freebase, crack, rock), methamphetamine (crystal meth, meth, crystal, jib, speed, ice, tina, side), and other amphetamine-like substances (including prescription stimulants)
Epidemiology
- Second-most commonly used illicit substance after marijuana
Pathophysiology
- All stimulants work on the dopamine system
| Stimulant | Mechanism | Half-life | Routes of administration |
|---|---|---|---|
| Cocaine | decreased dopamine re-uptake | 30 to 120 minutes | depends on the form |
| Powder cocaine | snorted, but can be mixed with water and injected | ||
| Crack cocaine | smoked, but can be mixed with an acid and injected | ||
| Freebase | similar to crack, but may explode when smoked | ||
| Methamphetamine | reverses dopamine reuptake, leading to increased excretion | wide variability, about 10 to 30 hours | powder can be snorted or pressed into a pill; base can be swallowed or injected; crystal meth can be smoked, dissolved and injected, or snorted |
Clinical Manifestations
Acute intoxication
- Common symptoms include tachycardia or bradycardia, pupillary dilatation, high or low blood pressure, sweating, chills, nausea or vomiting, weight loss, psychomotor agitation or retardation, muscular weakness, respiratory depression, chest pain, arrhythmias, confusion, seizures, dyskinesia, dystonia, and coma
- Severe intoxication may cause mania, paranoia, severe delirium, hypertension, agitation, sweating, formication and skin picking, choreoathetosis, and ataxia
Stimulant-induced psychosis
- Schizophrenia complicates about 15 to 25% of chronic stimulant use within 2 to 5 years
- Unclear what the causal relationship is between stimulants and schizophrenia
Other sequelae
- Cardiovascular or cerebrovascular disease, including myocardial infarction, stroke, and acute kidney injury
- Psychiatric diseases including psychosis, depression, and suicidal ideation
- Increased risk of HIV and hepatitis C
- Death
Withdrawal
- Symptoms include depressed mood, vivid dreams, fatigue, insomnia, hypersomnia, cravings, psychomotor agitation or impairment, increased appetite, agitation, irritability, and cognitive impairment
Investigations
Urine drug screen
- Cocaine metabolites are detectable for about 3 to 5 days
- False positives: none
- Methamphetamines may be detectable for 3 to 5 days, with some variability
- False positives: nasal inhalers, ADHD medications, bupropion, trazodone, chlorpromazine, promethazine, ranitidine
Management
Intoxication
- Generally focussed on supportive care
Withdrawal
- Generally focussed on supportive care, including good nutrition
- Cognitive behavioural therapy and sleep hygiene may be helpful
Chronic treatment
- There is no good evidence in favour of any pharmacologic treatment, and medication-based treatment is generally not recommended
- N-acetylcysteine may prevent relapse
- Disulfiram may treat cocaine use disorders
- Modafinil may be useful
- The main focus is on psychosocial treatments, including contingency management, cognitive behavioural therapy, motivational interviewing, relapse prevention, and psychodynamic therapy
- Long-term abstinence is around 30 to 50% for people in treatment, with 40-50% dropout rate
- Contingency planning with or without cognitive behavioural therapy seems to be the most promising
