Drug interactions
Homatropine + Oxybutynin
Severity: Moderate
Homatropine 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
Homatropine is an antimuscarinic and its effects add to those of oxybutynin. This may produce dry mouth, constipation, urinary retention, blurred vision and confusion, with systemic effects depending on the route used.
What this interaction means in plain words
Homatropine 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.
Homatropine belongs to Genitourinary; Oxybutynin belongs to Genitourinary.
Why it happens
Additive antimuscarinic receptor blockade.
What to do
Monitor for anticholinergic toxicity and avoid duplicate antimuscarinic therapy where an alternative exists; use the lowest effective doses.
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 Oxybutynin
Other interactions of Homatropine
- Amantadine + Homatropine Moderate
- Amitriptyline + Homatropine Moderate
- Atropine + Homatropine Moderate
- Benztropine + Homatropine Moderate
- Bethanechol + Homatropine Moderate
- Chlorpromazine + Homatropine Moderate
Frequently asked questions
Can I take Homatropine with Oxybutynin?
MediHelp rates the interaction as moderate. Homatropine 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. Homatropine is an antimuscarinic and its effects add to those of oxybutynin. This may produce dry mouth, constipation, urinary retention, blurred vision and confusion, with systemic effects depending on the route used.
How serious is the interaction between Homatropine 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: Monitor for anticholinergic toxicity and avoid duplicate antimuscarinic therapy where an alternative exists; use the lowest effective doses.
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.
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