What the FDA labels say about taking them together
Ethinyl estradiol/norelgestromin and tizanidine
Ethinyl estradiol/norelgestromin's FDA label of April 16, 2026 names tizanidine in its drug interactions section; the tizanidine labels PlainMeds reads (3) do not name ethinyl estradiol/norelgestromin. The ethinyl estradiol/norelgestromin label: “Concomitant use with ethinyl estradiol-containing CHCs may increase systemic exposure of other drugs.”
Check it at the source: the ethinyl estradiol/norelgestromin FDA label on DailyMed (effective April 16, 2026, Zydus Pharmaceuticals USA Inc.); the tizanidine FDA label on DailyMed (effective January 2, 2026, Legacy Pharma USA, Inc.).
What does the ethinyl estradiol/norelgestromin label say about tizanidine?
Ethinyl estradiol/norelgestromin label, drug interactionsContraceptives on Other Drugs CHCs containing EE may inhibit the metabolism of other compounds (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations.
Gwyn Lo label (Viatris Specialty LLC, July 6, 2026), drug interactionsConcomitant use with ethinyl estradiol-containing CHCs may increase systemic exposure of other drugs (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole).
Source: FDA drug label (Gwyn Lo, NDA219990), Viatris Specialty LLC, effective July 6, 2026 (SPL set e92741f4-87fe-429f-b5b5-c558ed5f4fa9), via openFDA
Source: FDA drug label (norelgestromin and ethinyl estradiol), Zydus Pharmaceuticals USA Inc., effective April 16, 2026 (SPL set 10fa1458-c8ed-4197-922a-1ba7271d2b02), via openFDA; the full label on DailyMed
What does the tizanidine label say about ethinyl estradiol/norelgestromin?
Tizanidine's label (effective January 2, 2026) and its 2 other brand-application labels do not name ethinyl estradiol/norelgestromin in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Zanaflex), Legacy Pharma USA, Inc., effective January 2, 2026 (SPL set 60c27d35-7349-4fc6-86ad-70fffdbe3e08), 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
| Ethinyl estradiol/norelgestromin | Tizanidine | |
|---|---|---|
| Labeled for | Birth control | Muscle spasms and spasticity |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $37.16 per patch 150-35 mcg/day patch | $0.0331 per tablet 4 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