Diazepam

Long-acting GABA-A PAM·Neurology - Sedatives & Hypnotics

Acute anxiety, muscle spasms, alcohol withdrawal, status epilepticus

PBSBENZOValium, Antenex, Ducene2 mg tabletS4+1

Max Dose

Varies

Half-life

20–100 h

Dependence

HIGH RISK

Metabolites

ACTIVE

Rapid Summary

Overview

Highly lipophilic, long-acting benzodiazepine. Rapid onset but features a massive half-life and active metabolites that accumulate in fat and liver tissue over days.

Maximum Dose

Max varies entirely by indication (40 mg/day for anxiety, massive doses >100mg for acute alcohol withdrawal).

Clinical Focus

Do not use in the elderly or those with severe liver failure. The drug will accumulate, causing a multi-day coma and falls.

Bottom Line

Diazepam is a long-acting benzodiazepine for acute anxiety, seizures, and alcohol withdrawal, but accumulates with repeated dosing (active metabolites) and carries high dependence and respiratory depression risk.

Formulation & Access

Brand Names

Valium, Antenex, Ducene

Oral Routes

Tablets (2 mg, 5 mg).

Parenteral

Ampoules (10 mg/2 mL) for IV use. Avoid IM (erratic absorption and painful).

Prescribing & PBS

Unrestricted General Benefit (S4). High abuse potential.

Indications & Use

Primary

PBSTGA

Acute anxiety, muscle spasms, alcohol withdrawal, status epilepticus.

Clinical Place

The gold standard for alcohol withdrawal due to 'auto-tapering' (long half-life prevents sudden withdrawal seizures).

Quick reference

Class & Role

Long-acting GABA-A PAM — Highly lipophilic, long-acting benzodiazepine.

Route / Formulation

Tablets (2 mg, 5 mg). (Valium, Antenex, Ducene)

Usual Dose & Max

PO 2-10 mg BD to QID. Max varies entirely by indication (40 mg/day for anxiety, massive doses >100mg for acute alcohol withdrawal).

Key Indication Doses

Anxiety / Muscle Spasm: PO 2-10 mg BD to QID. Alcohol Withdrawal: PO 10-20 mg q1-2h PRN using a symptom-triggered CIWA-Ar scale. Status Epilepticus: IV 5-10 mg pushed slowly (2-5 mg/min). Max 20 mg. Elderly / Hepatic: Avoid or halve dose. Prefer Oxazepam or Lorazepam.

Best Uses

Avoid / Cautions

Severe respiratory insufficiency, sleep apnea, Myasthenia Gravis. Pregnancy Category C (Risk of 'Floppy Infant Syndrome').

Key Risks

Neurological: Profound sedation, anterograde amnesia, ataxia, falls, cognitive blunting. CRITICAL — Tolerance, physical dependence, and severe withdrawal seizures upon abrupt cessation. Respiratory: Respiratory depression (especially if given rapidly IV or mixed with opioids). Cardiovascular: Hypotension (mostly IV).

Key Interactions

Opioids, Barbiturates, Alcohol. Additive and synergistic CNS/respiratory depression. Major cause of overdose deaths. CYP3A4 and CYP2C19 inhibitors (e.g., Omeprazole, Cimetidine) significantly prolong half-life.

Monitoring

Monitor SpO2 and RR if using IV. Assess for over-sedation and falls risk in all patients. No specific routine laboratory tests required.

Clinical Pearl

Diazepam is preferred in alcohol withdrawal because you load the patient with a massive dose on day 1 and 2, and then simply stop. The 100+ hour half-life of the metabolites tapers the drug out of the body naturally over a week, preventing seizures without needing complex weaning schedules.

Access

Valium, Antenex, Ducene2 mg tablet

Brand: Valium, Antenex, Ducene
Formulation: Tablets (2 mg, 5 mg)