Nirmatrelvir/Ritonavir and Sildenafil Interaction
Drug interaction information between Nirmatrelvir/Ritonavir and Sildenafil.
Nirmatrelvir/Ritonavir and Sildenafil have a documented major interaction in FDA labeling.
FDA drug labeling documents a major-severity interaction between Nirmatrelvir/Ritonavir and Sildenafil. 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
This combination makes sildenafil stay in your body longer and at higher levels, which can cause your blood pressure to drop too low.
FDA Label Information
Pulmonary hypertension agents (PDE5 inhibitors) sildenafil (Revatio ® ) ↑ sildenafil Co-administration of sildenafil with PAXLOVID is contraindicated for use in pulmonary hypertension due to the potential for sildenafil associated adverse events, including visual abnormalities hypotension, prolonged erection, and syncope [see Contraindications (4) ] . sildenafil, tadalafil, vardenafil ↑ sildenafil ↑ tadalafil ↑ vardenafil Dosage adjustment is recommended for use of sildenafil, tadalafil or vardenafil with PAXLOVID when used for erectile dysfunction.
Nirmatrelvir/Ritonavir Also Interacts With
- Simvastatin major
- Lovastatin major
- Carbamazepine major
- Rifampin major
- Lurasidone major
Sildenafil Also Interacts With
- Ketoconazole major
- Erythromycin major
- Itraconazole major
- Darunavir major
- Hydralazine/Isosorbide Dinitrate major
Frequently Asked Questions
What SPL severity band is on file for Nirmatrelvir/Ritonavir + Sildenafil?
Compiled FDA labeling labels this pair major. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Nirmatrelvir/Ritonavir has 86 labeled pairs on file vs Sildenafil's 10. In the major band specifically: Nirmatrelvir/Ritonavir has 23 (also Simvastatin, Lovastatin, Carbamazepine, Rifampin); Sildenafil has 6 (also Ketoconazole, Erythromycin, Itraconazole, Darunavir).
What mechanism field is on file for Nirmatrelvir/Ritonavir and Sildenafil?
This combination makes sildenafil stay in your body longer and at higher levels, which can cause your blood pressure to drop too low.
Nirmatrelvir/Ritonavir carries more major-labeled pairs than Sildenafil
SPL source-record counts only. This page's band is major · classes on file: Nirmatrelvir/Ritonavir (Antiviral (Protease Inhibitor Combination)); Sildenafil (PDE5 Inhibitor).
Nirmatrelvir/Ritonavir has 23 major-labeled pairs vs Sildenafil's 6.
23 major · 30 moderate · 33 minor · 86 total
- Other major peers for Nirmatrelvir/Ritonavir
- Simvastatin
- Lovastatin
- Carbamazepine
- Rifampin
6 major · 1 moderate · 3 minor · 10 total
- Other major peers for Sildenafil
- Ketoconazole
- Erythromycin
- Itraconazole
- Darunavir
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.