Probenecid and Levofloxacin Interaction
Drug interaction information between Probenecid and Levofloxacin.
Probenecid and Levofloxacin have a documented major interaction in FDA labeling.
FDA drug labeling documents a major-severity interaction between Probenecid and Levofloxacin. 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
Probenecid slows down the kidneys' ability to remove levofloxacin, which keeps the antibiotic in your system for a longer time.
What To Do
No dose changes are usually needed, but your doctor will monitor your progress.
FDA Label Information
7.8 Probenecid and Cimetidine No significant effect of probenecid or cimetidine on the Cmax of levofloxacin was observed in a clinical study involving healthy volunteers. The AUC and t 1/2 of levofloxacin were higher while CL/F and CLR were lower during concomitant treatment of levofloxacin with probenecid or cimetidine compared to levofloxacin alone. However, these changes do not warrant dosage adjustment for levofloxacin when probenecid or cimetidine is co-administered.
Probenecid Also Interacts With
- Ketorolac major
- Amoxicillin moderate
- Amoxicillin/Clavulanate moderate
- Ceftazidime/Avibactam moderate
- Cefuroxime moderate
Levofloxacin Also Interacts With
- Cimetidine major
- Theophylline moderate
- Warfarin minor
- Cyclosporine minor
- Digoxin minor
Frequently Asked Questions
Can I take Probenecid and Levofloxacin together?
This is a major interaction. No dose changes are usually needed, but your doctor will monitor your progress.
How serious is the interaction between Probenecid and Levofloxacin?
This interaction is classified as "major" severity by the FDA. Major interactions may be life-threatening or cause serious side effects.
Why do Probenecid and Levofloxacin interact?
Probenecid slows down the kidneys' ability to remove levofloxacin, which keeps the antibiotic in your system for a longer time.
Understanding the Probenecid and Levofloxacin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a major-severity interaction. Probenecid belongs to the Uricosuric Agent class and Levofloxacin belongs to the Fluoroquinolone Antibiotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Probenecid slows down the kidneys' ability to remove levofloxacin, which keeps the antibiotic in your system for a longer time. 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. Probenecid has 37 total documented interactions on file in this dataset, and Levofloxacin has 8. 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: No dose changes are usually needed, but your doctor will monitor your progress. 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 Probenecid or Levofloxacin 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.