Oxybutynin and Itraconazole Interaction
Drug interaction information between Oxybutynin and Itraconazole.
Oxybutynin and Itraconazole have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Oxybutynin and Itraconazole. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Itraconazole interferes with how your body processes oxybutynin. This can increase the amount of oxybutynin in your bloodstream.
What To Do
Your doctor should monitor your response to the medication and may adjust your dose if needed.
FDA Label Information
Other inhibitors of the cytochrome P450 3A4 enzyme system, such as antimycotic agents (e.g., itraconazole and miconazole) or macrolide antibiotics (e.g., erythromycin and clarithromycin), may alter oxybutynin mean pharmacokinetic parameters (i.e., C max and AUC).
Oxybutynin Also Interacts With
- Ketoconazole minor
- Erythromycin minor
- Clarithromycin minor
- Metoclopramide minor
- Carbamazepine minor
Itraconazole Also Interacts With
- Isavuconazonium major
- Lurasidone major
- Pimozide major
- Methadone major
- Midazolam major
Frequently Asked Questions
Can I take Oxybutynin and Itraconazole together?
This is a minor interaction. Your doctor should monitor your response to the medication and may adjust your dose if needed.
How serious is the interaction between Oxybutynin and Itraconazole?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Oxybutynin and Itraconazole interact?
Itraconazole interferes with how your body processes oxybutynin. This can increase the amount of oxybutynin in your bloodstream.
Understanding the Oxybutynin and Itraconazole Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Oxybutynin belongs to the Anticholinergic / Antispasmodic class and Itraconazole belongs to the Azole Antifungal class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Itraconazole interferes with how your body processes oxybutynin. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Oxybutynin has 7 total documented interactions on file in this dataset, and Itraconazole has 116. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor should monitor your response to the medication and may adjust your dose if needed. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Oxybutynin or Itraconazole based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.