Alprazolam to Clonazepam Conversion for Anxiety
The equivalent dose of Klonopin (clonazepam) for a patient taking 0.5 mg of Xanax (alprazolam) twice daily (total 1 mg/day) is 0.5 mg of clonazepam once or twice daily (total 0.5-1 mg/day).
Conversion Rationale
- Clonazepam has a longer half-life (20-80 hours) compared to alprazolam (12 hours), allowing for less frequent dosing and more continuous control of anxiety 1
- The FDA-approved dosing for clonazepam in anxiety disorders (panic disorder) starts at 0.25 mg twice daily with a target dose of 1 mg/day 2
- When switching from alprazolam to clonazepam, a 1:1 dose equivalence is generally appropriate, with the advantage of reducing dosing frequency due to clonazepam's longer duration of action 3
Advantages of Switching to Clonazepam
- Clonazepam's longer half-life permits less frequent dosing than alprazolam, providing more continuous control of anxiety 4
- Approximately 82% of patients switched from alprazolam to clonazepam rated clonazepam as "better" due to decreased frequency of administration and reduced interdose anxiety 3
- Clonazepam may reduce the "clock-watching phenomenon" that can occur with shorter-acting benzodiazepines like alprazolam 5
Dosing Recommendations
- Initial conversion: Start with 0.5 mg of clonazepam once daily (preferably at bedtime) or 0.25 mg twice daily 2
- Titration: If needed, dose may be increased after 3 days in increments of 0.125-0.25 mg twice daily 2
- Maximum dose: While the maximum FDA-approved dose for panic disorder is 4 mg/day, most patients respond well to 1 mg/day 2
- Geriatric patients: Start with lower doses and observe closely for side effects 2
Clinical Pearls
- Clonazepam can be used to facilitate withdrawal from alprazolam dependency, with studies showing this method is safe and effective with minimal withdrawal symptoms 6
- Both medications are effective for anxiety disorders at comparable doses, but clonazepam's pharmacokinetic profile may provide advantages for patients experiencing interdose anxiety with alprazolam 3
- Monitor for common benzodiazepine side effects including sedation, cognitive impairment, and potential for dependence 4
- Regular reassessment of the need for continued benzodiazepine treatment is recommended 2
Important Considerations
- Discontinuation of either benzodiazepine should be gradual to avoid withdrawal symptoms 2, 7
- For clonazepam, decrease by 0.125 mg twice daily every 3 days when discontinuing 2
- Some patients may require an even slower taper schedule 2, 7
- Avoid abrupt discontinuation of either medication due to risk of withdrawal symptoms 2, 7