Drug interactions
Diphenhydramine + Levetiracetam
Severity: Moderate
Diphenhydramine and Levetiracetam: 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
Diphenhydramine is markedly sedating, and levetiracetam also commonly causes somnolence. Together they may increase drowsiness and impair coordination, especially in older adults.
What this interaction means in plain words
Diphenhydramine and Levetiracetam 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; Levetiracetam belongs to Central Nervous System.
Why it happens
Additive CNS depressant effects.
What to do
Counsel patients to avoid driving or hazardous tasks while taking both, and use the lowest effective diphenhydramine dose or a non-sedating alternative.
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 Levetiracetam
Other interactions of Diphenhydramine
Frequently asked questions
Can I take Diphenhydramine with Levetiracetam?
MediHelp rates the interaction as moderate. Diphenhydramine and Levetiracetam 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 is markedly sedating, and levetiracetam also commonly causes somnolence. Together they may increase drowsiness and impair coordination, especially in older adults.
How serious is the interaction between Diphenhydramine and Levetiracetam?
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 or hazardous tasks while taking both, and use the lowest effective diphenhydramine dose or a non-sedating alternative.
What other medicines interact with Levetiracetam?
MediHelp also lists interactions of Levetiracetam with, for example, Oliceridine, Opium tincture, Sodium oxybate. The full list is on the Levetiracetam page.
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