Drug interactions
Diphenhydramine + Perampanel
Severity: Moderate
Diphenhydramine and Perampanel: 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
Perampanel can cause somnolence, dizziness and gait disturbance, and diphenhydramine adds sedation. The combination can impair alertness and coordination and raise fall risk.
What this interaction means in plain words
Diphenhydramine and Perampanel 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.
Diphenhydramine belongs to Respiratory; Perampanel belongs to Central Nervous System.
Why it happens
Additive CNS depression from AMPA receptor antagonism and histamine H1 blockade.
What to do
Counsel patients to avoid driving and hazardous tasks; prefer a non-sedating antihistamine and monitor for excess drowsiness.
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 Diphenhydramine
Other interactions of Perampanel
- Apalutamide + Perampanel Major
- Enzalutamide + Perampanel Major
- Alprazolam + Perampanel Moderate
- Amisulpride + Perampanel Moderate
- Amobarbital + Perampanel Moderate
- Asenapine + Perampanel Moderate
Frequently asked questions
Can I take Diphenhydramine with Perampanel?
MediHelp rates the interaction as moderate. Diphenhydramine and Perampanel 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. Perampanel can cause somnolence, dizziness and gait disturbance, and diphenhydramine adds sedation. The combination can impair alertness and coordination and raise fall risk.
How serious is the interaction between Diphenhydramine and Perampanel?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Counsel patients to avoid driving and hazardous tasks; prefer a non-sedating antihistamine and monitor for excess drowsiness.
What other medicines interact with Diphenhydramine?
MediHelp also lists interactions of Diphenhydramine with, for example, Alfentanil, Belladonna and opium, Benzhydrocodone / acetaminophen. The full list is on the Diphenhydramine page.
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