What the FDA labels say about taking them together
Erythromycin and sildenafil
Erythromycin's FDA label of August 1, 2024 names sildenafil in its drug interactions section, and sildenafil's label names erythromycin too. The sildenafil label: “CYP3A4 inhibitors: Increase VIAGRA exposure ▪ Ritonavir:”
Check it at the source: the erythromycin FDA label on DailyMed (effective August 1, 2024, Teva Pharmaceuticals USA, Inc.); the sildenafil FDA label on DailyMed (effective November 17, 2023, Viatris Specialty LLC).
What does the erythromycin label say about sildenafil?
Erythromycin label, drug interactionsSildenafil (Viagra ® ) Erythromycin has been reported to increase the systemic exposure (AUC) of sildenafil.
Source: FDA drug label (Erythromycin), Teva Pharmaceuticals USA, Inc., effective August 1, 2024 (SPL set 75a0bd5a-d09f-483b-bfd8-f8343b149eb2), via openFDA; the full label on DailyMed
What does the sildenafil label say about erythromycin?
Sildenafil label, drug interactionsCYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase VIAGRA exposure ( 2.4 , 7.4 , 12.3 ) ▪ Ritonavir:
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
| Erythromycin | Sildenafil | |
|---|---|---|
| Labeled for | Bacterial infections, Acne | Erectile dysfunction, Pulmonary arterial hypertension |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $1.96 per tablet 250 mg tablet | $0.132 per tablet 100 mg tablet |
| Shortage now | No current entry | 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