Drug interactions
Darifenacin + Orphenadrine
Severity: Moderate
Darifenacin and Orphenadrine: 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
Orphenadrine has substantial anticholinergic activity, which adds to that of darifenacin. Patients may experience dry mouth, constipation, urinary retention, tachycardia, blurred vision, and confusion.
What this interaction means in plain words
Darifenacin and Orphenadrine 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 muscarinic receptor antagonism.
What to do
Avoid the combination in older adults where possible; otherwise monitor for anticholinergic toxicity and 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 Darifenacin
Frequently asked questions
Can I take Darifenacin with Orphenadrine?
MediHelp rates the interaction as moderate. Darifenacin and Orphenadrine 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. Orphenadrine has substantial anticholinergic activity, which adds to that of darifenacin. Patients may experience dry mouth, constipation, urinary retention, tachycardia, blurred vision, and confusion.
How serious is the interaction between Darifenacin and Orphenadrine?
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 the combination in older adults where possible; otherwise monitor for anticholinergic toxicity and use the lowest effective doses.
What other medicines interact with Darifenacin?
MediHelp also lists interactions of Darifenacin with, for example, Atazanavir, Bethanechol, Clarithromycin. The full list is on the Darifenacin page.
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