Lorazepam Dosing for Seizure Management
For seizure management, the recommended dose of lorazepam is 0.1 mg/kg intravenously (maximum 4 mg per dose), which may be repeated after 5-10 minutes if seizures persist. 1, 2
Adult Dosing
- IV administration: 0.1 mg/kg (maximum 4 mg per dose), may be repeated after 10-15 minutes if seizures continue 1
- For status epilepticus in adults (≥18 years): 4 mg given slowly (2 mg/min); may administer additional 4 mg dose after 10-15 minutes if seizures continue 1
- Close monitoring of respiratory status is essential as respiratory depression is a significant risk 1
Pediatric Dosing
- IV administration: 0.1 mg/kg (maximum 4 mg per dose) 2
- For convulsive status epilepticus: 0.1 mg/kg IV (maximum 2 mg); may repeat after at least 1 minute (maximum 2 doses) 2
- For non-convulsive status epilepticus: 0.05 mg/kg IV (maximum 1 mg); may repeat every 5 minutes (maximum 4 doses) 2
- Maintenance dosing after resolution of status epilepticus: 0.05 mg/kg (maximum 1 mg) IV every 8 hours for 3 doses 2
Alternative Routes of Administration
- Rectal administration: 0.5 mg/kg up to 20 mg (useful when IV access is unavailable, though absorption may be erratic) 2
- Intranasal administration: 0.1 mg/kg (maximum 4 mg) has been shown to be non-inferior to IV administration in children 3
- IM administration is generally not recommended for seizure management due to risk of tissue necrosis 2
Special Considerations
- Equipment to maintain patent airway must be immediately available prior to administration 1
- Monitor oxygen saturation and respiratory effort, as there is increased risk of apnea when combined with other sedative agents 2, 4
- Flumazenil may be used to reverse life-threatening respiratory depression but will also counteract anticonvulsant effects and may precipitate seizures 2
- Underdosing of lorazepam (less than 4 mg in adults >40 kg) has been associated with increased progression to refractory status epilepticus 5
Dosing in Special Populations
- Elderly patients and those with hepatic disease: No dosage adjustments needed for acute administration 1
- Patients with renal disease: No dosage adjustments needed for acute administration, but caution with frequent dosing over short periods 1
Common Pitfalls
- Underdosing is common and associated with treatment failure; ensure appropriate weight-based dosing 5
- Failure to have respiratory support immediately available 1
- Delayed administration; lorazepam should be given promptly for seizure management 2
- Not following lorazepam with a long-acting anticonvulsant (such as levetiracetam or phenytoin) when treating status epilepticus 2
Lorazepam has been shown to be as effective as diazepam-phenytoin combination in controlling pediatric convulsive status epilepticus, with the advantage of being a single drug 6. Even in neonates with refractory seizures, lorazepam at 0.05 mg/kg (up to 0.15 mg/kg total) has demonstrated efficacy 7.