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What the FDA labels say about taking them together

Ethinyl estradiol/levonorgestrel and felbamate

Ethinyl estradiol/levonorgestrel's FDA label of August 27, 2026 names felbamate in its drug interactions section; the felbamate label PlainMeds reads does not name ethinyl estradiol/levonorgestrel. The ethinyl estradiol/levonorgestrel label: “Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate …”

Check it at the source: the ethinyl estradiol/levonorgestrel FDA label on DailyMed (effective August 27, 2026, Exeltis USA, Inc.); the felbamate FDA label on DailyMed (effective August 15, 2025, Viatris Specialty LLC).

What does the ethinyl estradiol/levonorgestrel label say about felbamate?

Ethinyl estradiol/levonorgestrel label, drug interactions

Continue backup contraception for 28 days after discontinuing the enzyme inducer to maintain contraceptive reliability. Examples Aprepitant, barbiturates, bosentan, carbamazepine, efavirenz, felbamate, griseofulvin, oxcarbazepine, phenytoin, rifampin, primidone, phenylbutazone, rifabutin, rufinamide, topiramate, products containing St. John's wort, and certain protease inhibitors (see separate section on protease inhibitors below).

Balcoltra label (Avion Pharmaceuticals, December 5, 2025), drug interactions

Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St. John’s wort.

Source: FDA drug label (Balcoltra, NDA208612), Avion Pharmaceuticals, effective December 5, 2025 (SPL set 752ab698-4b48-4614-8016-d1d33ee7c007), via openFDA

Source: FDA drug label (Twirla, NDA204017), Agile Therapeutics, Inc., effective June 30, 2026 (SPL set bcaf8db0-1750-425d-b008-255b5e7a9cc6), via openFDA

Source: FDA drug label (Tyblume), Exeltis USA, Inc., effective August 27, 2026 (SPL set b2482d51-d606-4aaa-8af4-19e4fe2f8872), via openFDA; the full label on DailyMed

What does the felbamate label say about ethinyl estradiol/levonorgestrel?

Felbamate's label (effective August 15, 2025) does not name ethinyl estradiol/levonorgestrel in these sections. A label lists what its studies and reports found; it is not a complete list.

Source: FDA drug label (Felbatol), NDA020189 (Mylan Speciality Lp), as published by Viatris Specialty LLC, effective August 15, 2025 (SPL set 2f522701-397a-11de-8a39-0800200c9a66), 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

19Ethinyl estradiol/levonorgestrel generic labelers
9Felbamate generic labelers
Ethinyl estradiol/levonorgestrelFelbamate
Labeled forBirth controlSeizures and epilepsy
Boxed warningYesYes
Pharmacy cost (NADAC)$0.154 per tablet 28 tablet$1.00 per tablet 600 mg tablet
Shortage nowNo current entryNo current entry

Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)

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