What is the recommended dose of lorazepam (Ativan) given sublingually (SL) for seizure management?

Recommended Dosing of Sublingual Lorazepam for Seizure Management

For seizure management in adults, the recommended sublingual (SL) lorazepam dose is 1 mg (range 0.5-2 mg), which has shown effectiveness in controlling prolonged and repetitive seizures without serious adverse events. 1

Dosing Recommendations by Age Group

Adults:

• Initial dose: 1 mg SL (range 0.5-2 mg)
• May repeat if seizures continue after 10-15 minutes
• Maximum total dose: 2 mg per episode

Children:

• Dose range: 0.05-0.15 mg/kg SL 2
• Typical effective dose: 0.1 mg/kg SL
• Maximum single dose: 4 mg

Administration Guidelines

1. Preparation:

   • Use lorazepam oral concentrate solution
   • Place directly under the tongue
   • Have patient/caregiver hold solution under tongue until absorbed
   • Do not swallow immediately

2. Timing:

   • Administer as soon as possible for prolonged seizures (>5 minutes)
   • For repetitive seizures, administer after the first seizure to prevent subsequent episodes

3. Storage considerations:

   • Lorazepam solution typically requires refrigeration
   • This can limit accessibility in emergency situations 1
   • Consider portable cooling options if refrigeration limits access

Efficacy Data

Sublingual lorazepam has demonstrated good efficacy in seizure management:

• 70% effectiveness in stopping prolonged seizures within 5 minutes
• 66% effectiveness in preventing further seizures in patients with repetitive seizure patterns 1

For comparison, IV lorazepam at the recommended dose of 0.05-0.1 mg/kg (maximum 4 mg) has shown:

• 76% efficacy in controlling seizures with a single dose 3
• Significantly higher rates of refractory status epilepticus when underdosed 4

Safety Considerations

Common Side Effects:

• Sedation (31% of patients may develop moderate/severe sedation) 1
• Drowsiness
• Unsteadiness

Serious Adverse Events:

• Respiratory depression (less common with SL than IV administration)
• Risk of respiratory depression increases when combined with other sedative agents 5

Important Precautions:

• Monitor respiratory status after administration
• Be prepared to provide respiratory support if needed
• Flumazenil may be administered to reverse life-threatening respiratory depression, but this will also counteract the anticonvulsant effects and may precipitate recurrence of seizures 5

Clinical Pearls

1. Sublingual lorazepam offers an accessible alternative to rectal diazepam or expensive intranasal formulations for home management of seizures.

2. Patient/caregiver education is essential for proper administration and monitoring.

3. The need for refrigeration is a significant limitation, with 44% of patients reporting this limited treatment access 1.

4. Having this emergency treatment available provides psychological benefit, with 79% of patients reporting increased feelings of safety 1.

5. Underdosing lorazepam for seizure management is associated with progression to refractory status epilepticus, emphasizing the importance of appropriate dosing 4.

Sublingual lorazepam represents a practical, effective option for acute seizure management, particularly in settings where IV access is challenging or unavailable.