Drug interactions
Fesoterodine + Orphenadrine
Severity: Moderate
Fesoterodine and Orphenadrine: 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
Orphenadrine has substantial anticholinergic activity, so combining it with fesoterodine increases the risk of dry mouth, constipation, urinary retention, confusion and tachycardia. Elderly patients are particularly vulnerable.
What this interaction means in plain words
Fesoterodine and Orphenadrine 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 antimuscarinic effects.
What to do
Avoid the combination in older patients where possible; otherwise monitor for urinary retention, cognitive changes and constipation.
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
Frequently asked questions
Can I take Fesoterodine with Orphenadrine?
MediHelp rates the interaction as moderate. Fesoterodine and Orphenadrine 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. Orphenadrine has substantial anticholinergic activity, so combining it with fesoterodine increases the risk of dry mouth, constipation, urinary retention, confusion and tachycardia. Elderly patients are particularly vulnerable.
How serious is the interaction between Fesoterodine and Orphenadrine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination in older patients where possible; otherwise monitor for urinary retention, cognitive changes and constipation.
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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