What the FDA labels say about taking them together
Ritonavir and sildenafil
Ritonavir's FDA label of July 23, 2026 names sildenafil in its contraindications section, and sildenafil's label names ritonavir too. The ritonavir label: “Sildenafil when used for the treatment of pulmonary arterial hypertension (Revatio ®) is contraindicated due to the potential for sildenafil-associated adverse events, including visual abnormalities, hypotension …”
Check it at the source: the ritonavir FDA label on DailyMed (effective July 23, 2026, AbbVie Inc.); the sildenafil FDA label on DailyMed (effective November 17, 2023, Viatris Specialty LLC).
What does the ritonavir label say about sildenafil?
Ritonavir label, contraindications… cisapride ○ HMG-CoA Reductase Inhibitors: lovastatin, simvastatin ○ Microsomal triglyceride transfer protein (MTTP) Inhibitor: lomitapide ○ Non-opioid Analgesic (selective blocker of Na v 1.8 sodium channels): suzetrigine ○ PDE5 Inhibitor: sildenafil (Revatio ® ) when used for the treatment of pulmonary arterial hypertension ○ Sedative/Hypnotics: triazolam, orally administered midazolam
Ritonavir label, drug interactionsConcomitant Drug Class/Drug Name: PDE5 Inhibitors: avanafil sildenafil, tadalafil, vardenafil; Effect on Concentration of Ritonavir or Concomitant Drug: ↑ avanafil ↑ sildenafil ↑ tadalafil ↑ vardenafil; Clinical Comment: Sildenafil when used for the treatment of pulmonary arterial hypertension (Revatio ®) is contraindicated due to the potential for sildenafil-associated adverse events, including visual abnormalities, hypotension, prolonged erection, and syncope [see Contraindications () ]. Do not use ritonavir with avanafil because a safe and effective avanafil dosage regimen has not been established. …
Source: FDA drug label (Norvir), AbbVie Inc., effective July 23, 2026 (SPL set 2849298e-de6e-47bb-8194-56e075b33fc3), via openFDA; the full label on DailyMed
What does the sildenafil label say about ritonavir?
Sildenafil label, drug interactionsCYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase VIAGRA exposure ( 2.4 , 7.4 , 12.3 ) ▪ Ritonavir:
Sildenafil label, warnings and precautionsIn patients taking strong CYP inhibitors, such as ritonavir, sildenafil exposure is increased.
Vybrique label (IBSA Pharma Inc., July 8, 2026), drug interactionsDRUG INTERACTIONS VYBRIQUE can potentiate the hypotensive effects of nitrates, alpha blockers, and antihypertensives. ( 4.1 , 5.5 , 7.1 , 7.2 , 7.3 , 12.2 ) With concomitant use of alpha blockers, initiate VYBRIQUE at 25 mg dose. ( 2.2 ) CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin) increase VYBRIQUE exposure.
Source: FDA drug label (Vybrique, NDA210858), IBSA Pharma Inc., effective July 8, 2026 (SPL set 9213fec1-e0c0-4ef7-9718-d97922a3f4d8), via openFDA
Source: FDA drug label (Viagra), Viatris Specialty LLC, effective November 17, 2023 (SPL set d905dc8d-917f-4ea3-a4ee-a1ecf6967d4e), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Ritonavir | Sildenafil | |
|---|---|---|
| Labeled for | HIV | Erectile dysfunction, Pulmonary arterial hypertension |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.607 per tablet 100 mg tablet | $0.132 per tablet 100 mg tablet |
| Shortage now | A presentation being discontinued | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once