Drug interactions
Dimenhydrinate + Flavoxate
Severity: Moderate
Dimenhydrinate 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
Dimenhydrinate contains diphenhydramine, which is strongly anticholinergic, and flavoxate has antimuscarinic activity. Combined use may increase dry mouth, constipation, urinary retention, blurred vision and confusion.
What this interaction means in plain words
Dimenhydrinate 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.
Dimenhydrinate belongs to Respiratory; Flavoxate belongs to Genitourinary.
Why it happens
Additive antimuscarinic pharmacodynamic effects.
What to do
Avoid in older or cognitively impaired patients and in those with urinary retention; otherwise monitor for anticholinergic 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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Dimenhydrinate and Flavoxate, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Dimenhydrinate
Frequently asked questions
Can I take Dimenhydrinate with Flavoxate?
MediHelp rates the interaction as moderate. Dimenhydrinate 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. Dimenhydrinate contains diphenhydramine, which is strongly anticholinergic, and flavoxate has antimuscarinic activity. Combined use may increase dry mouth, constipation, urinary retention, blurred vision and confusion.
How serious is the interaction between Dimenhydrinate 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 in older or cognitively impaired patients and in those with urinary retention; otherwise monitor for anticholinergic effects.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
