Drug interactions
Benztropine + Fesoterodine
Severity: Moderate
Benztropine and Fesoterodine: 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
Benztropine is a potent antimuscarinic and combined use with fesoterodine increases dry mouth, constipation, urinary retention, blurred vision, heat intolerance and delirium, especially in older adults.
What this interaction means in plain words
Benztropine and Fesoterodine 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.
Benztropine belongs to Central Nervous System; Fesoterodine belongs to Genitourinary.
Why it happens
Additive antimuscarinic pharmacodynamic effects.
What to do
Avoid combining where possible in elderly patients; otherwise use the lowest effective doses and monitor for urinary retention, constipation and cognitive effects.
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 Benztropine
- Benztropine + Memantine-donepezil Major
- Abobotulinumtoxina + Benztropine Moderate
- Amantadine + Benztropine Moderate
- Amitriptyline + Benztropine Moderate
- Amoxapine + Benztropine Moderate
- Atropine iv / + Benztropine Moderate
Frequently asked questions
Can I take Benztropine with Fesoterodine?
MediHelp rates the interaction as moderate. Benztropine and Fesoterodine 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. Benztropine is a potent antimuscarinic and combined use with fesoterodine increases dry mouth, constipation, urinary retention, blurred vision, heat intolerance and delirium, especially in older adults.
How serious is the interaction between Benztropine and Fesoterodine?
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 combining where possible in elderly patients; otherwise use the lowest effective doses and monitor for urinary retention, constipation and cognitive effects.
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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