What the FDA labels say about taking them together
Cobimetinib and erythromycin
Cobimetinib's FDA label of July 29, 2026 names erythromycin in its drug interactions section; the erythromycin labels PlainMeds reads (4) do not name cobimetinib. The cobimetinib label: “If concurrent short term (14 days or less) use of moderate CYP3A inhibitors including certain antibiotics is unavoidable for patients who are taking COTELLIC 60 mg, reduce COTELLIC dose to 20 mg.”
Check it at the source: the cobimetinib FDA label on DailyMed (effective July 29, 2026, Genentech, Inc.); the erythromycin FDA label on DailyMed (effective August 1, 2024, Teva Pharmaceuticals USA, Inc.).
What does the cobimetinib label say about erythromycin?
Cobimetinib label, drug interactionsIf concurrent short term (14 days or less) use of moderate CYP3A inhibitors including certain antibiotics (e.g., erythromycin, ciprofloxacin) is unavoidable for patients who are taking COTELLIC 60 mg, reduce COTELLIC dose to 20 mg.
Source: FDA drug label (Cotellic), Genentech, Inc., effective July 29, 2026 (SPL set c387579e-cee0-4334-bd1e-73f93ac1bde6), via openFDA; the full label on DailyMed
What does the erythromycin label say about cobimetinib?
Erythromycin's label (effective August 1, 2024) and its 3 other brand-application labels do not name cobimetinib in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Erythromycin), Teva Pharmaceuticals USA, Inc., effective August 1, 2024 (SPL set 75a0bd5a-d09f-483b-bfd8-f8343b149eb2), 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
| Cobimetinib | Erythromycin | |
|---|---|---|
| Labeled for | n/a | Bacterial infections, Acne |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $1.96 per tablet 250 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