Drug interactions
Homatropine + Orphenadrin
Severity: Moderate
Homatropine and Orphenadrin: 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 orphenadrine has substantial anticholinergic activity, so their effects add together. This can produce dry mouth, constipation, urinary retention, blurred vision, tachycardia and confusion.
What this interaction means in plain words
Homatropine and Orphenadrin 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; Orphenadrin belongs to Musculoskeletal.
Why it happens
Additive antimuscarinic pharmacodynamic effects.
What to do
Monitor for anticholinergic toxicity and use lower doses in older patients; avoid in patients with glaucoma or urinary retention.
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 Orphenadrin
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 Orphenadrin?
MediHelp rates the interaction as moderate. Homatropine and Orphenadrin 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 orphenadrine has substantial anticholinergic activity, so their effects add together. This can produce dry mouth, constipation, urinary retention, blurred vision, tachycardia and confusion.
How serious is the interaction between Homatropine and Orphenadrin?
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 use lower doses in older patients; avoid in patients with glaucoma or urinary retention.
What other medicines interact with Orphenadrin?
MediHelp also lists interactions of Orphenadrin with, for example, Alfentanil, Amobarbital, Benzhydrocodone / acetaminophen. The full list is on the Orphenadrin page.
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