Section 01 · Monograph
Lorazepam
Reviewed Nov 2026FDA label
AtivanBenzodiazepine
- Forms
- Tab: 0.5, 1, 2mg | IV/IM: 2, 4mg/mL
- Dose
- Status epilepticus: 4mg IV slowly; may repeat once in 10-15 min
- MOA
- ↑GABA-A Cl- channel frequency
Black Box Warning
- Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma and death
- Abuse, misuse and addiction risk
- Dependence and withdrawal reactions
Indications
- Status epilepticus (IV)FDA-labeled
- Preanesthetic sedation (IV/IM)FDA-labeled
- Anxiety disorders (oral)FDA-labeled
Off-Label Uses
- Acute agitationOff-label
- Chemotherapy-related nauseaOff-label
Mechanism of Action
- Benzodiazepine that enhances GABA-A receptor chloride channel opening frequency; longer anticonvulsant duration than IV diazepam due to less redistribution
Full Dosing
Adult / usual
- Status epilepticus: 4mg IV given slowly (about 2mg/min; 0.1mg/kg); may repeat once after 10-15 minutes
- Dilute IV lorazepam 1:1 with compatible diluent before injection; refrigerate vials
- Keep airway equipment available
Contraindications
- Acute narrow-angle glaucoma
- Sleep apnea syndrome or severe respiratory insufficiency (IV, unless ventilated)
- Hypersensitivity, including to benzyl alcohol or propylene glycol components
Drug Interactions
- Opioids and other CNS depressants: boxed warning for profound sedation
- Valproate and probenecid raise lorazepam levels
- Alcohol: additive CNS depression
Adverse Effects
- Respiratory depression and sedation
- Hypotension
- Paradoxical agitation
- Propylene glycol toxicity with prolonged high-dose infusion
- Dependence and withdrawal
Monitoring Parameters
- Respiratory rate, oxygen saturation, blood pressure
- Sedation level
- Osmolar gap and lactate with prolonged infusion
Pregnancy & Lactation
- Late-pregnancy exposure can cause neonatal sedation or withdrawal
- Excreted in milk; monitor infants for sedation