Drug interactions
Fesoterodine + Primidone
Severity: Moderate
Fesoterodine and Primidone: 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
Primidone is metabolized to phenobarbital and acts as a CYP3A4 inducer, which can reduce levels of the active fesoterodine metabolite. Reduced bladder symptom control may result.
What this interaction means in plain words
Fesoterodine and Primidone 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.
Fesoterodine belongs to Genitourinary; Primidone belongs to Central Nervous System.
Why it happens
CYP3A4 induction by primidone and its phenobarbital metabolite increases clearance of fesoterodine's active metabolite.
What to do
Monitor for reduced efficacy and titrate fesoterodine within the labeled dose range if needed.
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 Fesoterodine
Other interactions of Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Fesoterodine with Primidone?
MediHelp rates the interaction as moderate. Fesoterodine and Primidone 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. Primidone is metabolized to phenobarbital and acts as a CYP3A4 inducer, which can reduce levels of the active fesoterodine metabolite. Reduced bladder symptom control may result.
How serious is the interaction between Fesoterodine and Primidone?
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 reduced efficacy and titrate fesoterodine within the labeled dose range if needed.
What other medicines interact with Fesoterodine?
MediHelp also lists interactions of Fesoterodine with, for example, Bethanechol, Clozapine, Levoketoconazole. The full list is on the Fesoterodine page.
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