Drug interactions
Methocarbamol + Phenobarbital
Severity: Moderate
Methocarbamol and Phenobarbital: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Phenobarbital causes sedation and methocarbamol adds to central depression, increasing drowsiness and impaired coordination. The risk is greater at higher doses and in older or debilitated patients.
What this interaction means in plain words
Methocarbamol and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive CNS depressant effects.
What to do
Monitor for oversedation and reduce the methocarbamol dose if needed. Counsel patients to avoid driving and alcohol.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Methocarbamol
Frequently asked questions
Can I take Methocarbamol with Phenobarbital?
MediHelp rates the interaction as moderate. Methocarbamol and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Phenobarbital causes sedation and methocarbamol adds to central depression, increasing drowsiness and impaired coordination. The risk is greater at higher doses and in older or debilitated patients.
How serious is the interaction between Methocarbamol and Phenobarbital?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for oversedation and reduce the methocarbamol dose if needed. Counsel patients to avoid driving and alcohol.
What other medicines interact with Methocarbamol?
MediHelp also lists interactions of Methocarbamol with, for example, Alfentanil, Amobarbital, Belladonna and opium. The full list is on the Methocarbamol page.
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