Oxybutynin and Erythromycin Interaction
Drug interaction information between Oxybutynin and Erythromycin.
Oxybutynin and Erythromycin have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Oxybutynin and Erythromycin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Erythromycin slows down the process your body uses to get rid of oxybutynin. This can cause the level of oxybutynin in your blood to rise higher than normal.
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
- Clarithromycin minor
- Itraconazole minor
- Metoclopramide minor
- Carbamazepine minor
Erythromycin Also Interacts With
- Eplerenone major
- Pitavastatin major
- Risperidone major
- Sildenafil major
- Lefamulin moderate
Frequently Asked Questions
What SPL severity band is on file for Oxybutynin + Erythromycin?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Erythromycin has 63 labeled pairs on file vs Oxybutynin's 7. In the minor band specifically: Oxybutynin has 7 (also Ketoconazole, Clarithromycin, Itraconazole, Metoclopramide); Erythromycin has 53 (also Acetaminophen/Oxycodone, Alprazolam, Atorvastatin, Bromocriptine).
What mechanism field is on file for Oxybutynin and Erythromycin?
Erythromycin slows down the process your body uses to get rid of oxybutynin. This can cause the level of oxybutynin in your blood to rise higher than normal.
Erythromycin carries more major-labeled pairs than Oxybutynin
SPL source-record counts only. This page's band is minor · classes on file: Oxybutynin (Anticholinergic / Antispasmodic); Erythromycin (Macrolide Antibiotic).
Erythromycin has 4 major-labeled pairs vs Oxybutynin's 0. This page itself is in the minor band, not the major band.
0 major · 0 moderate · 7 minor · 7 total
- Other minor peers for Oxybutynin
- Ketoconazole
- Clarithromycin
- Itraconazole
- Metoclopramide
4 major · 6 moderate · 53 minor · 63 total
- Other minor peers for Erythromycin
- Acetaminophen/Oxycodone
- Alprazolam
- Atorvastatin
- Bromocriptine
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.