Tadalafil and Clarithromycin Interaction
Drug interaction information between Tadalafil and Clarithromycin.
Tadalafil and Clarithromycin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Tadalafil and Clarithromycin. 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
Clarithromycin stops the body from breaking down tadalafil properly. This leads to higher levels of tadalafil in your blood, which can increase the risk of side effects.
What To Do
Use this combination with caution. Your doctor may need to change your dose of tadalafil.
FDA Label Information
Phosphodiesterase inhibitors: Sildenafil Tadalafil Vardenafil Use With Caution Sildenafil, Tadalafil, Vardenafil: Each of these phosphodiesterase inhibitors is primarily metabolized by CYP3A, and CYP3A will be inhibited by concomitant administration of clarithromycin. Co-administration of clarithromycin with sildenafil, tadalafil, or vardenafil will result in increased exposure of these phosphodiesterase inhibitors.
Tadalafil Also Interacts With
- Hydralazine/Isosorbide Dinitrate major
- Nirmatrelvir/Ritonavir moderate
- Amlodipine minor
- Metoprolol minor
- Tamsulosin minor
Clarithromycin Also Interacts With
- Quetiapine major
- Pioglitazone major
- Fluconazole major
- Cyclosporine major
- Lurasidone major
Frequently Asked Questions
Can I take Tadalafil and Clarithromycin together?
This is a moderate interaction. Use this combination with caution. Your doctor may need to change your dose of tadalafil.
How serious is the interaction between Tadalafil and Clarithromycin?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Tadalafil and Clarithromycin interact?
Clarithromycin stops the body from breaking down tadalafil properly. This leads to higher levels of tadalafil in your blood, which can increase the risk of side effects.
Understanding the Tadalafil and Clarithromycin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Tadalafil belongs to the PDE5 Inhibitor class and Clarithromycin belongs to the Macrolide Antibiotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Clarithromycin stops the body from breaking down tadalafil properly. 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. Tadalafil has 25 total documented interactions on file in this dataset, and Clarithromycin has 81. 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: Use this combination with caution. 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 Tadalafil or Clarithromycin 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.