What the FDA labels say about taking them together
Nelfinavir and norethindrone
Nelfinavir's FDA label of December 11, 2025 names norethindrone in its drug interactions section, and norethindrone's label names nelfinavir too. The nelfinavir label: “Concentrations of ethinyl estradiol and norethindrone were decreased when coadministered with VIRACEPT. Alternative or additional contraceptive measures should be used when oral contraceptives containing ethinyl …”
Check it at the source: the nelfinavir FDA label on DailyMed (effective December 11, 2025, AGOURON); the norethindrone FDA label on DailyMed (effective January 31, 2026, Glenmark Pharmaceuticals Inc., USA).
What does the nelfinavir label say about norethindrone?
Nelfinavir label, drug interactionsConcomitant Drug Class/Drug Name: Ethinyl estradiol Norethindrone; Effect on Concentration: ↓ ethinyl estradiol ↓ norethindrone; Clinical Comment: Concentrations of ethinyl estradiol and norethindrone were decreased when coadministered with VIRACEPT. Alternative or additional contraceptive measures should be used when oral contraceptives containing ethinyl estradiol or norethindrone and VIRACEPT are coadministered.
Source: FDA drug label (VIRACEPT), AGOURON, effective December 11, 2025 (SPL set e72c2bc6-9462-4a2e-8e1d-b97592376cbd), via openFDA; the full label on DailyMed
What does the norethindrone label say about nelfinavir?
Norethindrone label, drug interactionsSignificant decreases in systemic concentrations of progestin have been noted in cases of co-administration with some HIV protease inhibitors (e.g., nelfinavir, ritonavir, darunavir/ritonavir, (fos)amprenavir/ritonavir, lopinavir/ritonavir, and tipranavir/ritonavir), some HCV protease inhibitors (e.g., boceprevir and telaprevir), and some non-nucleoside reverse transcriptase inhibitors (e.g., nevirapine, efavirenz).
Source: FDA drug label (Norethindrone), Glenmark Pharmaceuticals Inc., USA, effective January 31, 2026 (SPL set 0d2f8fea-3675-40d2-afd9-9fcb148dbd4b), 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
| Nelfinavir | Norethindrone | |
|---|---|---|
| Labeled for | HIV | Birth control |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.290 per tablet 5 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