Drug interactions
Itraconazole + Oxybutynin
Severity: Moderate
Itraconazole 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
Itraconazole is a potent CYP3A4 inhibitor and has been shown to increase oxybutynin exposure. This may intensify anticholinergic adverse effects such as dry mouth, constipation, drowsiness and confusion.
What this interaction means in plain words
Itraconazole 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.
Itraconazole belongs to Anti Fungals; Oxybutynin belongs to Genitourinary.
Why it happens
Inhibition of intestinal and hepatic CYP3A4 metabolism of oxybutynin.
What to do
Monitor for anticholinergic adverse effects and consider reducing the oxybutynin dose during itraconazole therapy.
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 Itraconazole
- Alfuzosin + Itraconazole Contraindicated
- Alprazolam + Itraconazole Contraindicated
- Avanafil + Itraconazole Contraindicated
- Conivaptan + Itraconazole Contraindicated
- Dihydroergotamine intranasal + Itraconazole Contraindicated
- Dihydroergotamine + Itraconazole Contraindicated
Frequently asked questions
Can I take Itraconazole with Oxybutynin?
MediHelp rates the interaction as moderate. Itraconazole 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. Itraconazole is a potent CYP3A4 inhibitor and has been shown to increase oxybutynin exposure. This may intensify anticholinergic adverse effects such as dry mouth, constipation, drowsiness and confusion.
How serious is the interaction between Itraconazole 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 adverse effects and consider reducing the oxybutynin dose during itraconazole therapy.
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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