Substance Use Disorders

Alcohol Use Disorder

•    Definition:

o    Problematic pattern of alcohol use → impairment/distress.

o    Criteria include loss of control, tolerance, withdrawal, neglect of roles.

•    Complications:

o    Wernicke’s encephalopathy:

    Triad: ophthalmoplegia, ataxia, confusion.

    Caused by thiamine deficiency; medical emergency.

o    Korsakoff’s syndrome:

    Anterograde amnesia, confabulation.

    Often irreversible.

•    Management pearls:

o    Always give thiamine before glucose to prevent precipitating Wernicke’s.

o    Oral or parenteral high-dose thiamine if at risk.

•    CIWA (Clinical Institute Withdrawal Assessment) scale:

o    Used to assess and guide treatment of alcohol withdrawal severity.

Alcohol Withdrawal Timeline

•    6–12 hours:

o    Tremor, anxiety, sweating, nausea.

•    12–48 hours:

o    Seizures (generalised tonic-clonic).

•    48–72 hours:

o    Delirium tremens: agitation, confusion, hallucinations, autonomic instability (↑ HR, BP, temp).

•    Treatment:

o    Benzodiazepines (e.g., chlordiazepoxide, diazepam).

o    Thiamine, fluids, electrolyte correction.

Other Substance Use Disorders

Opioids

•    Clinical features:

o    Euphoria, sedation, miosis ("pinpoint pupils"), respiratory depression.

•    Withdrawal:

o    Lacrimation, yawning, piloerection, diarrhoea, muscle aches.

•    Treatment:

o    Naloxone for overdose (short half-life; may require repeated doses).

o    Maintenance: methadone, buprenorphine.

Stimulants (e.g., cocaine, amphetamines)

•    Effects:

o    Euphoria, hypervigilance, psychosis, agitation, hypertension, seizures.

•    Withdrawal:

o    Depression ("crash"), hypersomnia, fatigue, craving.

•    Management:

o    Supportive, monitor for cardiovascular complications.

Cannabis

•    Features:

o    Amotivation, impaired short-term memory, anxiety, paranoia.

•    Complications:

o    Cannabis-induced psychosis.

o    Hyperemesis syndrome (cyclical vomiting relieved by hot showers).

Benzodiazepines

•    Dependence risk: especially with long-term use.

•    Withdrawal symptoms:

o    Anxiety, tremor, insomnia, perceptual disturbances, seizures (can be life-threatening).

•    Treatment:

o    Gradual tapering using long-acting benzo (e.g., diazepam).

General Management Principles

•    Brief interventions & motivational interviewing:

o    Enhance motivation to change, especially in early stages.

•    Detoxification programmes:

o    Medically supervised withdrawal, with psychological and social support.

•    Relapse prevention medications:

o    Acamprosate: reduces craving; start post-detox.

o    Disulfiram: aversion therapy; causes acetaldehyde reaction if alcohol ingested.

o    Naltrexone: opioid antagonist; reduces relapse risk (caution in liver disease).

Extra Revision Pearls

•    Disulfiram contraindicated in severe cardiac disease and hepatic insufficiency.

•    Methadone QT prolongation risk → monitor ECG.

•    Cocaine = strong vasoconstrictor → risk of MI and stroke even in young users.

•    Always consider polysubstance abuse (common in practice).

•    Hepatitis B, C, and HIV screening important in IV drug users.