Drug interactions
Dimenhydrinate + Phenobarbital
Severity: Moderate
Dimenhydrinate 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 and dimenhydrinate both depress the CNS, so together they increase drowsiness and impair coordination and alertness. Elderly patients and those with respiratory disease are at higher risk.
What this interaction means in plain words
Dimenhydrinate 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 depression from GABA-A potentiation and H1 antagonism.
What to do
Monitor for excessive sedation and counsel on avoiding driving and alcohol. Reduce doses if oversedation develops.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Dimenhydrinate and Phenobarbital, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Dimenhydrinate
Frequently asked questions
Can I take Dimenhydrinate with Phenobarbital?
MediHelp rates the interaction as moderate. Dimenhydrinate 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 and dimenhydrinate both depress the CNS, so together they increase drowsiness and impair coordination and alertness. Elderly patients and those with respiratory disease are at higher risk.
How serious is the interaction between Dimenhydrinate 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 excessive sedation and counsel on avoiding driving and alcohol. Reduce doses if oversedation develops.
What other medicines interact with Dimenhydrinate?
MediHelp also lists interactions of Dimenhydrinate with, for example, Belladonna and opium, Brexanolone, Calcium / magnesium / potassium / sodium oxybates. The full list is on the Dimenhydrinate page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
