Can nabilone be given 6 hours apart?

Nabilone Dosing Interval

Yes, nabilone can be given 6 hours apart, as the drug has a plasma half-life of approximately 2 hours, making a 6-hour dosing interval pharmacologically appropriate for maintaining therapeutic levels. 1

Pharmacokinetics of Nabilone

Nabilone is a synthetic cannabinoid with the following pharmacokinetic properties:

• Completely absorbed from the gastrointestinal tract when administered orally
• Peak plasma concentrations are achieved within 2 hours after oral administration
• Plasma half-life of nabilone is approximately 2 hours
• Effects are evident within 60-90 minutes and persist for 8-12 hours 1, 2

The duration of clinical effects (8-12 hours) is longer than would be expected from the plasma half-life (2 hours), suggesting that active metabolites may contribute to the pharmacological effects. This supports the possibility of using dosing intervals of 6 hours while maintaining therapeutic effect. 3

Established Dosing Regimens

Current clinical guidelines and FDA labeling support flexible dosing intervals for nabilone:

• For breakthrough chemotherapy-induced nausea and vomiting, nabilone can be dosed at 1-2 mg PO every 6 hours 4
• Standard dosing in clinical practice has included twice daily (every 12 hours) regimens 5
• Clinical trials have used dosing regimens of 1-2 mg twice daily 6

Clinical Considerations for 6-Hour Dosing

When administering nabilone every 6 hours, consider the following:

1. Monitor for cumulative effects: Although the plasma half-life is short, metabolites have a much longer half-life (approximately 35 hours), which may lead to accumulation with frequent dosing 1

2. Watch for side effects: Common side effects include:

   • Drowsiness (60-70% of patients)
   • Dizziness/vertigo (60-70% of patients)
   • Dry mouth
   • Hypotension
   • Potential for psychoactive effects 6

3. Tolerance development: Tolerance to some effects (euphoria, dry mouth) develops rapidly, usually within the first two days of treatment, but the relaxant effects may persist 2

Special Populations and Considerations

• Elderly patients: Use with caution as they may be more sensitive to CNS effects
• Renal/hepatic impairment: The effects of renal and hepatic dysfunction on nabilone metabolism have not been well studied 1
• Drug interactions: The simultaneous use of nabilone with alcohol or barbiturates may produce additive depressive effects on CNS function 1

Practical Dosing Recommendation

For most clinical scenarios requiring more frequent dosing than twice daily:

• Start with 1 mg every 6 hours
• Monitor response and side effects
• Adjust dose as needed (up to 2 mg every 6 hours if tolerated)
• Consider returning to twice daily dosing once symptoms are controlled

Remember that patients should remain under supervision of a responsible adult while using nabilone due to its potential psychoactive effects, especially when initiating more frequent dosing schedules. 1