Drug interactions
Fesoterodine + Trospium
Severity: Moderate
Fesoterodine and Trospium: 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 are antimuscarinics for overactive bladder, so using them together duplicates therapy without proven added benefit. Anticholinergic adverse effects such as dry mouth, constipation and urinary retention are increased.
What this interaction means in plain words
Fesoterodine and Trospium 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; Trospium belongs to Genitourinary.
Why it happens
Additive muscarinic receptor blockade.
What to do
Avoid combining two antimuscarinic bladder agents; optimise a single drug or switch to a different class. Monitor residual urine and bowel function if combined.
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 Trospium
- Clozapine + Trospium Major
- Pramlintide + Trospium Major
- Thioridazine + Trospium Major
- Trihexyphenidyl + Trospium Major
- Aclidinium + Trospium Moderate
- Amantadine + Trospium Moderate
Other interactions of Fesoterodine
Frequently asked questions
Can I take Fesoterodine with Trospium?
MediHelp rates the interaction as moderate. Fesoterodine and Trospium 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 are antimuscarinics for overactive bladder, so using them together duplicates therapy without proven added benefit. Anticholinergic adverse effects such as dry mouth, constipation and urinary retention are increased.
How serious is the interaction between Fesoterodine and Trospium?
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 two antimuscarinic bladder agents; optimise a single drug or switch to a different class. Monitor residual urine and bowel function if combined.
What other medicines interact with Trospium?
MediHelp also lists interactions of Trospium with, for example, Clozapine, Pramlintide, Thioridazine. The full list is on the Trospium page.
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