14th February 2025

Clinical features of alcohol and substance misuse

Short and long-term effects

Clinical features associated with abuse of alcohol and key illicit drugs are shown in Table 1. Other commonly misused drugs include inhalants, hallucinogens, anabolic steroids and prescribed drugs.

Drug	General effect and toxicity	Specific long-term health risks
Alcohol	Depressant: neurological deficits in attention, concentration, consciousness Antisocial behaviour, e.g. aggression, disinhibition	Poor dental hygiene, obesity, malnutrition Gastrointestinal and liver disorders Neurological: peripheral neuropathy, Wernicke-Korsakoff syndrome
Cannabis Also, marijuana, Mary-J, pot, grass, dope, hashish	Impaired attention, concentration, memory Nausea, postural hypotension, anxiety Delirium, acute psychosis	Cognitive impairment Schizophrenia, social anxiety (↑ risk) Chronic bronchitis and exacerbation of other respiratory conditions
Amphetamine derivatives E.g. speed, crystal meth, MDMA (methylenedioxymethamphetamine), ecstasy	Cerebral oedema Skin excoriation and lesions Trismus (lockjaw), bruxism (teeth grinding)	Dental and gum disease (“meth mouth”)
Features in common: amphetamine and cocaine	Hyperarousal, hypervigilance, anxiety, paranoia, hallucinations, agitation, psychosis Hypertension, hypotension, tachycardia, chest pain, myocardial infarction Hyperthermia, sweating, mydriasis Serotonin syndrome Focal neurology, seizure, stroke, ICH Rhabdomyolysis	Cardiac: cardiomyopathy, arrhythmias, ACS, sudden cardiac death Serotonin syndrome when used with other serotonergic drugs, e.g. SSRIs Inhalation: chronic bronchitis and exacerbation of other respiratory conditions
Cocaine	Formication (tactile hallucination of “skin crawling”)	Insufflation (snorting): epistaxis, nasal septal ulceration and perforation Inhalation (smoking): suspicious burns, “crack lip” and “crack thumb” Injection: site infection, abscess, necrosis, septicaemia, blood-borne diseases (e.g. HIV, HBV, HCV)
Opioids e.g. heroin, morphine, oxycodone, opium	Euphoria and pain management Altered consciousness: confusion to coma, sedation, coma Miosis (pinpoint pupils) Respiratory depression, death	Injection: site infection, abscess, necrosis, septicaemia, blood-borne diseases (e.g. HIV, HBV, HCV) Weight loss, insomnia, memory impairment, chronic constipation, vomiting

Drug

General effect and toxicity

Specific long-term health risks

Alcohol

Depressant: neurological deficits in attention, concentration, consciousness

Antisocial behaviour, e.g. aggression, disinhibition

Poor dental hygiene, obesity, malnutrition

Gastrointestinal and liver disorders

Neurological: peripheral neuropathy, Wernicke-Korsakoff syndrome

Cannabis

Also, marijuana, Mary-J, pot, grass, dope, hashish

Impaired attention, concentration, memory

Nausea, postural hypotension, anxiety

Delirium, acute psychosis

Cognitive impairment

Schizophrenia, social anxiety (↑ risk)

Chronic bronchitis and exacerbation of other respiratory conditions

Amphetamine derivatives

E.g. speed, crystal meth, MDMA (methylenedioxymethamphetamine), ecstasy

Cerebral oedema

Skin excoriation and lesions

Trismus (lockjaw), bruxism (teeth grinding)

Dental and gum disease (“meth mouth”)

Features in common: amphetamine and cocaine

Hyperarousal, hypervigilance, anxiety, paranoia, hallucinations, agitation, psychosis

Hypertension, hypotension, tachycardia, chest pain, myocardial infarction

Hyperthermia, sweating, mydriasis

Serotonin syndrome

Focal neurology, seizure, stroke, ICH

Rhabdomyolysis

Cardiac: cardiomyopathy, arrhythmias, ACS, sudden cardiac death

Serotonin syndrome when used with other serotonergic drugs, e.g. SSRIs

Inhalation: chronic bronchitis and exacerbation of other respiratory conditions

Cocaine

Formication (tactile hallucination of “skin crawling”)

Insufflation (snorting): epistaxis, nasal septal ulceration and perforation

Inhalation (smoking): suspicious burns, “crack lip” and “crack thumb”

Injection: site infection, abscess, necrosis, septicaemia, blood-borne diseases (e.g. HIV, HBV, HCV)

Opioids
e.g. heroin, morphine, oxycodone, opium

Euphoria and pain management

Altered consciousness: confusion to coma, sedation, coma

Miosis (pinpoint pupils)

Respiratory depression, death

Injection: site infection, abscess, necrosis, septicaemia, blood-borne diseases (e.g. HIV, HBV, HCV)

Weight loss, insomnia, memory impairment, chronic constipation, vomiting

Table 1 Short and long-term effects of alcohol and key illicit drugs

For most of the above toxicity presentations, management is supportive, with a couple of exceptions:

Opioid toxicity: naloxone (opioid antagonist) is a life-saving treatment given in respiratory depression
Orally ingested drugs: activated charcoal can be given within 1 h of ingestion to prevent further absorption

Wernicke-Korsakoff syndrome

This is a reversible-to-irreversible cognitive deficit syndrome resulting from thiamine deficiency, often in the context of alcohol misuse. The classic triad of symptoms in Wernicke’s encephalopathy is acute confusion, gaze palsy and gait ataxia. Korsakoff’s syndrome describes the progression to chronic irreversible cognitive impairment. They can be thought of as a single condition with a spectrum of presentations.

Withdrawal

The most important substance withdrawal syndromes are with alcohol and opioids. These can occur unexpectedly in patients admitted for unrelated reasons, as they may not openly admit to heavy alcohol or opioid use.

Substance	Features of withdrawal	Management
Alcohol	Anxiety, agitation, tremor, sweating Nausea and vomiting Tactile, auditory and visual hallucinations or sensitivity Headache Delirium tremens (medical emergency; suspect with altered consciousness): confusion, seizures (increased risk with a background of epilepsy), coma, death Onset can be <24 h after last intake of alcohol, but altered consciousness typically appears >48 h after	Long-acting benzodiazepine: chlordiazepoxide, diazepam CIWA-Ar score monitoring
Opioid	Agitation Nausea and vomiting, diarrhoea, abdominal cramps Muscle cramps Sweating Mydriasis (dilated pupils) Rarely, arrhythmias Onset can be within hours or days and varies with opioid	Long-acting opioids (methadone or buprenorphine) Treat acute symptoms, e.g. loperamide, ondansetron, ibuprofen, dicycloverine (antispasmodic)

Substance

Features of withdrawal

Management

Alcohol

Anxiety, agitation, tremor, sweating

Nausea and vomiting

Tactile, auditory and visual hallucinations or sensitivity

Headache

Delirium tremens (medical emergency; suspect with altered consciousness): confusion, seizures (increased risk with a background of epilepsy), coma, death

Onset can be <24 h after last intake of alcohol, but altered consciousness typically appears >48 h after

Long-acting benzodiazepine: chlordiazepoxide, diazepam

CIWA-Ar score monitoring

Opioid

Agitation

Nausea and vomiting, diarrhoea, abdominal cramps

Muscle cramps

Sweating

Mydriasis (dilated pupils)

Rarely, arrhythmias

Onset can be within hours or days and varies with opioid

Long-acting opioids (methadone or buprenorphine)