Drug interactions
Hyoscyamine spray + Tolterodine
Severity: Moderate
Hyoscyamine spray and Tolterodine: 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
Oral or sublingual hyoscyamine spray is absorbed systemically and adds antimuscarinic effects to tolterodine. This increases risk of dry mouth, constipation, urinary retention and confusion.
What this interaction means in plain words
Hyoscyamine spray and Tolterodine 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 pharmacodynamic effects.
What to do
Avoid duplicate antimuscarinic therapy; monitor for anticholinergic toxicity and reduce doses as needed.
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 Hyoscyamine spray and Tolterodine, 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 Tolterodine
Frequently asked questions
Can I take Hyoscyamine spray with Tolterodine?
MediHelp rates the interaction as moderate. Hyoscyamine spray and Tolterodine 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. Oral or sublingual hyoscyamine spray is absorbed systemically and adds antimuscarinic effects to tolterodine. This increases risk of dry mouth, constipation, urinary retention and confusion.
How serious is the interaction between Hyoscyamine spray and Tolterodine?
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 duplicate antimuscarinic therapy; monitor for anticholinergic toxicity and reduce doses as needed.
What other medicines interact with Tolterodine?
MediHelp also lists interactions of Tolterodine with, for example, Clarithromycin, Clozapine, Cobicistat. The full list is on the Tolterodine 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.
