What is the best medication to administer in cases of accidental consumption of hallucinogenic substances?

Management of Accidental Hallucinogenic Consumption

For acute agitation or panic reactions from hallucinogenic ingestion, benzodiazepines—specifically diazepam or lorazepam—are the preferred pharmacological intervention, not antipsychotics. 1, 2

Initial Assessment and Supportive Care

The foundation of management involves supportive care with attention to airway, breathing, and circulation before any pharmacological intervention. 3

Key assessment priorities include:

• Rule out life-threatening mimics: Exclude hypoglycemia, hyponatremia, other metabolic derangements, and co-ingestions (particularly stimulants, anticholinergics, or sympathomimetics) that may present similarly 3
• Differentiate the specific hallucinogen: LSD produces combined hallucinations, pseudohallucinations and illusions; phencyclidine (PCP) can produce complex hallucinations resembling paranoid psychosis; other agents have characteristic patterns 1
• Monitor vital signs continuously: Watch for hyperpyrexia, hypertension, tachycardia, or seizures which require immediate intervention 2

Pharmacological Management Algorithm

For Mild to Moderate Agitation or Panic Reactions ("Bad Trip")

First-line approach: "Talking down" in a calm, supportive environment 2

• Place patient in a quiet, low-stimulation environment with reassuring interpersonal support 4
• This non-pharmacological approach often suffices for mild cases 2

If pharmacological intervention becomes necessary:

• Benzodiazepines are the drug class of choice 1, 2
• Diazepam: 2-10 mg IV/IM initially, repeat in 3-4 hours if necessary 5, 2
• Lorazepam: 2-4 mg IV slowly (alternative to diazepam) 3, 6
• Critical: Phenothiazines and antipsychotics are NOT preferred for sedation in hallucinogen intoxication 2

For Severe Agitation Requiring Immediate Control

Benzodiazepine dosing for severe cases:

• Diazepam: 5-10 mg IV/IM, may repeat in 3-4 hours 5
• Lorazepam: 2-4 mg IV administered slowly (2 mg/min), particularly effective when combined with supportive measures 3, 6
• Ensure airway equipment and ventilatory support are immediately available before administration 5, 6

For Seizures Secondary to Hallucinogen Toxicity

If convulsive seizures develop:

• Diazepam: 5-10 mg IV initially, may repeat at 10-15 minute intervals up to maximum 30 mg 5
• Lorazepam: 4 mg IV slowly (2 mg/min); if seizures continue after 10-15 minutes, may give additional 4 mg 6
• Maintain airway patency and have respiratory support immediately available 5, 6

For Hypertensive Crisis or Hyperpyrexia

These complications require aggressive supportive management beyond benzodiazepines:

• Benzodiazepines may help reduce sympathetic tone 2
• Active cooling measures for hyperpyrexia
• Antihypertensive agents as clinically indicated
• Continuous monitoring in intensive care setting 2

Special Considerations by Drug Class

LSD and Psilocybin (Serotonergic Hallucinogens)

• Generally physiologically safe with low toxicity 7
• Primary risk is psychological distress during acute intoxication 4
• Benzodiazepines for panic reactions; rarely require antipsychotics unless prolonged psychosis develops 1

Phencyclidine (PCP) and Dissociatives

• Higher risk of violent behavior and complex hallucinations 1
• May require higher or repeated benzodiazepine doses 2
• Monitor for hypertensive crisis and hyperpyrexia 2

Anticholinergic Hallucinogens (Datura, etc.)

• Present with anticholinergic toxidrome: delirium, hyperthermia, mydriasis, dry skin 8
• Benzodiazepines for agitation and seizures 5
• Physostigmine may be considered in severe cases (not covered in provided evidence, but standard practice)

Monitoring and Disposition

Observation period requirements:

• Minimum 4-6 hours for short-acting hallucinogens (LSD, psilocybin) after symptom resolution
• Extended observation for longer-acting agents or if complications occurred 4
• Monitor for emergence of delayed psychiatric symptoms 4

Discharge criteria:

• Patient calm and oriented
• Vital signs normalized
• No ongoing medical complications
• Safe disposition with responsible adult
• Follow-up arranged for any persistent psychiatric symptoms 4

Critical Pitfalls to Avoid

• Never use phenothiazines or typical antipsychotics as first-line sedation—benzodiazepines are preferred 2
• Do not administer benzodiazepines without ensuring airway equipment is immediately available, as respiratory depression can occur 5, 6
• Do not assume "just a bad trip"—always exclude dangerous mimics like anticholinergic toxicity, sympathomimetic overdose, or metabolic emergencies 3, 1
• Do not discharge patients prematurely—observe until fully calm and oriented with normalized vital signs 4
• Do not overlook co-ingestions, particularly stimulants, alcohol, or other CNS depressants that may complicate management 3, 1