What the FDA labels say about taking them together
Avanafil and nelfinavir
Avanafil's FDA label of December 17, 2025 names nelfinavir in its drug interactions section; nelfinavir's label does not name avanafil itself but warns about its class (PDE5 inhibitors). The avanafil label: “For patients taking concomitant strong CYP3A4 inhibitors, do not use avanafil.”
Check it at the source: the avanafil FDA label on DailyMed (effective December 17, 2025, Camber Pharmaceuticals, Inc.); the nelfinavir FDA label on DailyMed (effective December 11, 2025, AGOURON).
What does the avanafil label say about nelfinavir?
Avanafil label, drug interactionsOther potent inhibitors of CYP3A4 (e.g., itraconazole, clarithromycin, nefazadone, ritonavir, saquinavir, nelfinavir, indinavir, atanazavir and telithromycin) would be expected to have similar effects.
Avanafil label, warnings and precautionsFor patients taking concomitant strong CYP3A4 inhibitors (including ketoconazole, ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir and telithromycin), do not use avanafil [see Drug Interactions ( 7.2 )].
Source: FDA drug label (Avanafil), ANDA209266 (Hetero Labs Ltd V), as published by Camber Pharmaceuticals, Inc., effective December 17, 2025 (SPL set 1d04e17d-7399-430a-a8bb-fa1912b155e9), via openFDA; the full label on DailyMed
What does the nelfinavir label say about avanafil?
Nelfinavir's label does not name avanafil itself; it warns about its class (PDE5 inhibitors):
Nelfinavir label, contraindicationsPDE5 Inhibitors Sildenafil (Revatio ® ) [for treatment of pulmonary arterial hypertension] See Drug Interactions, Table 6 for coadministration of sildenafil and tadalafil when dosed for erectile dysfunction.
Nelfinavir label, drug interactionsCoadministration of VIRACEPT and drugs primarily metabolized by CYP3A (e.g., dihydropyridine calcium channel blockers, HMG-CoA reductase inhibitors, immunosuppressants, and PDE5 inhibitors) may result in increased plasma concentrations of such drugs that could increase or prolong both its therapeutic and adverse effects (see Tables 3 and 6 ).
Source: FDA drug label (VIRACEPT), AGOURON, effective December 11, 2025 (SPL set e72c2bc6-9462-4a2e-8e1d-b97592376cbd), 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
| Avanafil | Nelfinavir | |
|---|---|---|
| Labeled for | Erectile dysfunction | HIV |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $50.00 per tablet 200 mg tablet | n/a |
| 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