Drug interactions
Levetiracetam + Promethazine
Severity: Moderate
Levetiracetam and Promethazine: 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
Both drugs can cause drowsiness, dizziness and impaired coordination, so combined use may increase sedation and psychomotor impairment. Promethazine may also lower the seizure threshold, which is relevant in patients treated for epilepsy.
What this interaction means in plain words
Levetiracetam and Promethazine 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.
Levetiracetam belongs to Central Nervous System; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depression; phenothiazines may also lower seizure threshold, opposing anticonvulsant effect.
What to do
Counsel patients about drowsiness and avoid driving until the response is known. Monitor seizure control and consider an alternative antiemetic or antihistamine if seizures worsen.
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 Promethazine
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
- Amiodarone + Promethazine Major
- Amisulpride + Promethazine Major
Other interactions of Levetiracetam
Frequently asked questions
Can I take Levetiracetam with Promethazine?
MediHelp rates the interaction as moderate. Levetiracetam and Promethazine 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. Both drugs can cause drowsiness, dizziness and impaired coordination, so combined use may increase sedation and psychomotor impairment. Promethazine may also lower the seizure threshold, which is relevant in patients treated for epilepsy.
How serious is the interaction between Levetiracetam and Promethazine?
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 about drowsiness and avoid driving until the response is known. Monitor seizure control and consider an alternative antiemetic or antihistamine if seizures worsen.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Promethazine page.
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