Nitroglycerin and Tadalafil Interaction
Drug interaction information between Nitroglycerin and Tadalafil.
Nitroglycerin and Tadalafil have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Nitroglycerin and Tadalafil. 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
Tadalafil makes the blood-pressure-lowering effects of nitroglycerin much stronger. This can lead to a severe and unsafe decrease in your blood pressure.
What To Do
Do not use these medications at the same time, as the combination can cause life-threatening low blood pressure.
FDA Label Information
PDE-5-Inhibitors such as avanafil, sildenafil, vardenafil, and tadalafil have been shown to potentiate the hypotensive effects of organic nitrates.
Nitroglycerin Also Interacts With
- Dapsone Topical moderate
- Lidocaine Topical moderate
- Aspirin minor
- Sildenafil minor
- Heparin minor
Tadalafil Also Interacts With
- Hydralazine/Isosorbide Dinitrate major
- Clarithromycin moderate
- Nirmatrelvir/Ritonavir moderate
- Amlodipine minor
- Metoprolol minor
Frequently Asked Questions
Can I take Nitroglycerin and Tadalafil together?
This is a minor interaction. Do not use these medications at the same time, as the combination can cause life-threatening low blood pressure.
How serious is the interaction between Nitroglycerin and Tadalafil?
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 Nitroglycerin and Tadalafil interact?
Tadalafil makes the blood-pressure-lowering effects of nitroglycerin much stronger. This can lead to a severe and unsafe decrease in your blood pressure.
Understanding the Nitroglycerin and Tadalafil Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Nitroglycerin belongs to the Nitrate Vasodilator class and Tadalafil belongs to the PDE5 Inhibitor class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Tadalafil makes the blood-pressure-lowering effects of nitroglycerin much stronger. 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. Nitroglycerin has 8 total documented interactions on file in this dataset, and Tadalafil has 25. 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: Do not use these medications at the same time, as the combination can cause life-threatening low blood pressure. 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 Nitroglycerin or Tadalafil 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.