Does Losartan Potassium Interact with Erythromycin?
Losartan Potassium and Erythromycin have a moderate drug interaction according to U.S. FDA drug labeling data. AUC of active metabolite was not affected but AUC of losartan was increased by 30%. The mechanism involves cyp450 3a4 inhibition. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Moderate
- Erythromycin Class
- Macrolide
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Losartan Potassium and Erythromycin occurs because cyp450 3a4 inhibition. Clinically, this means auc of active metabolite was not affected but auc of losartan was increased by 30%. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Losartan Potassium and your doctor is considering prescribing Erythromycin (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider