What the FDA labels say about taking them together
Efavirenz and norethindrone
Norethindrone's FDA label of January 31, 2026 names efavirenz in its drug interactions section; the efavirenz label PlainMeds reads does not name norethindrone. The norethindrone label: “Some drugs or herbal products that may decrease the effectiveness of HCs include efavirenz, phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, rifabutin, rufinamide …”
Check it at the source: the efavirenz FDA label on DailyMed (effective March 31, 2024, Cipla USA Inc.); the norethindrone FDA label on DailyMed (effective January 31, 2026, Glenmark Pharmaceuticals Inc., USA).
What does the efavirenz label say about norethindrone?
Efavirenz's label (effective March 31, 2024) does not name norethindrone in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Efavirenz), Cipla USA Inc., effective March 31, 2024 (SPL set 92603fa5-7a2c-4bfb-9a70-aadb4fba952c), via openFDA; the full label on DailyMed
What does the norethindrone label say about efavirenz?
Norethindrone label, drug interactionsSome drugs or herbal products that may decrease the effectiveness of HCs include efavirenz, phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, rifabutin, rufinamide, aprepitant, and products containing St. John’s wort.
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
| Efavirenz | Norethindrone | |
|---|---|---|
| Labeled for | HIV | Birth control |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $1.28 per tablet 600 mg tablet | $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