Drug interactions
Fesoterodine + Flavoxate
Severity: Moderate
Fesoterodine and Flavoxate: 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
Fesoterodine is an antimuscarinic for overactive bladder, so adding flavoxate duplicates anticholinergic therapy. This raises the risk of dry mouth, constipation, urinary retention and blurred vision without clear added benefit.
What this interaction means in plain words
Fesoterodine and Flavoxate 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; Flavoxate belongs to Genitourinary.
Why it happens
Additive antimuscarinic pharmacodynamic effects.
What to do
Avoid combining bladder antimuscarinics unless clearly needed. If combined, monitor post-void residual volume and bowel function.
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 Flavoxate
- Clozapine + Flavoxate Major
- Abobotulinumtoxina + Flavoxate Moderate
- Aclidinium + Flavoxate Moderate
- Amantadine + Flavoxate Moderate
- Amitriptyline + Flavoxate Moderate
- Amoxapine + Flavoxate Moderate
Other interactions of Fesoterodine
Frequently asked questions
Can I take Fesoterodine with Flavoxate?
MediHelp rates the interaction as moderate. Fesoterodine and Flavoxate 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 is an antimuscarinic for overactive bladder, so adding flavoxate duplicates anticholinergic therapy. This raises the risk of dry mouth, constipation, urinary retention and blurred vision without clear added benefit.
How serious is the interaction between Fesoterodine and Flavoxate?
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 bladder antimuscarinics unless clearly needed. If combined, monitor post-void residual volume and bowel function.
What other medicines interact with Flavoxate?
MediHelp also lists interactions of Flavoxate with, for example, Clozapine, Abobotulinumtoxina, Aclidinium. The full list is on the Flavoxate page.
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