What is the lorazepam (Ativan) equivalent dose to clonazepam (Klonopin) 0.5 mg?

Lorazepam Equivalent to Clonazepam 0.5 mg

The equivalent dose of lorazepam (Ativan) to clonazepam (Klonopin) 0.5 mg is 0.25 mg, based on the established conversion ratio where clonazepam 2 mg equals lorazepam 1 mg. 1

Benzodiazepine Conversion Principles

When converting between benzodiazepines, several important pharmacological properties must be considered:

• Potency ratio: Clonazepam is approximately twice as potent as lorazepam, with clonazepam 2 mg equivalent to lorazepam 1 mg 1
• Duration of action: Clonazepam has a significantly longer half-life (30-40 hours) compared to lorazepam (10-20 hours) 1
• Onset of action: Lorazepam has a more rapid onset of action compared to clonazepam 2

Clinical Implications of Conversion

When switching from clonazepam to lorazepam, important considerations include:

• Dosing frequency: Due to lorazepam's shorter duration of action, the total daily dose should be divided into 2-3 administrations 1
• Monitoring needs: Patients should be monitored for withdrawal symptoms or over-sedation during the first 3-5 days after conversion 1
• Clinical effect: While the equivalent dose provides similar therapeutic effects, the clinical response may differ due to pharmacokinetic differences 3

Special Populations and Considerations

• Hepatic impairment: Consider starting with a lower dose of lorazepam in patients with liver dysfunction 1
• Elderly patients: Lower initial doses may be required due to altered metabolism 1
• Polypharmacy: Drug interactions may affect benzodiazepine metabolism and required dosing 1

Practical Conversion Approach

For a patient on clonazepam 0.5 mg:

1. Calculate lorazepam equivalent: 0.5 mg clonazepam = 0.25 mg lorazepam
2. Consider dividing the lorazepam dose if multiple daily doses are needed
3. Monitor for clinical response and adjust as needed

Common Pitfalls to Avoid

• Abrupt discontinuation: Never abruptly switch between benzodiazepines without proper tapering, as this can precipitate withdrawal symptoms 4
• Assuming identical clinical effects: Despite equivalent potency, the different pharmacokinetic profiles may result in different clinical responses 2
• Overlooking patient-specific factors: Age, comorbidities, and concomitant medications can significantly impact benzodiazepine metabolism and response 1