Drug interactions
Hyoscyamine + Oxybutynin
Severity: Moderate
Hyoscyamine and Oxybutynin: 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 are antimuscarinic drugs, so their effects add. This increases the risk of dry mouth, constipation, urinary retention, tachycardia, blurred vision and confusion.
What this interaction means in plain words
Hyoscyamine and Oxybutynin 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.
Hyoscyamine belongs to Genitourinary; Oxybutynin belongs to Genitourinary.
Why it happens
Additive antimuscarinic receptor blockade.
What to do
Avoid duplicate anticholinergic therapy; if both are needed, use the lowest effective doses and monitor for anticholinergic toxicity.
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 and Oxybutynin, 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 Oxybutynin
Other interactions of Hyoscyamine
- Amantadine + Hyoscyamine Moderate
- Amitriptyline + Hyoscyamine Moderate
- Aripiprazole + Hyoscyamine Moderate
- Atropine + Hyoscyamine Moderate
- Benztropine + Hyoscyamine Moderate
- Bethanechol + Hyoscyamine Moderate
Frequently asked questions
Can I take Hyoscyamine with Oxybutynin?
MediHelp rates the interaction as moderate. Hyoscyamine and Oxybutynin 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 are antimuscarinic drugs, so their effects add. This increases the risk of dry mouth, constipation, urinary retention, tachycardia, blurred vision and confusion.
How serious is the interaction between Hyoscyamine and Oxybutynin?
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 anticholinergic therapy; if both are needed, use the lowest effective doses and monitor for anticholinergic toxicity.
What other medicines interact with Oxybutynin?
MediHelp also lists interactions of Oxybutynin with, for example, Bethanechol, Clozapine, Potassium chloride. The full list is on the Oxybutynin 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.
