What the FDA labels say about taking them together
Afatinib and erythromycin
Afatinib's FDA label of November 13, 2025 names erythromycin in its drug interactions section; the erythromycin labels PlainMeds reads (4) do not name afatinib. The afatinib label: “Increase GILOTRIF by 10 mg per day as tolerated. Effect of P-glycoprotein (P-gp) Inhibitors and Inducers Concomitant taking of P-gp inhibitors with GILOTRIF can increase exposure to afatinib.”
Check it at the source: the afatinib FDA label on DailyMed (effective November 13, 2025, Boehringer Ingelheim Pharmaceuticals, Inc.); the erythromycin FDA label on DailyMed (effective August 1, 2024, Teva Pharmaceuticals USA, Inc.).
What does the afatinib label say about erythromycin?
Afatinib label, drug interactionsIncrease GILOTRIF by 10 mg per day as tolerated. ( 2.5 , 7 ) Effect of P-glycoprotein (P-gp) Inhibitors and Inducers Concomitant taking of P-gp inhibitors (including but not limited to ritonavir, cyclosporine A, ketoconazole, itraconazole, erythromycin, verapamil, quinidine, tacrolimus, nelfinavir, saquinavir, and amiodarone) with GILOTRIF can increase exposure to afatinib [see Clinical Pharmacology (12.3) ].
Source: FDA drug label (Gilotrif), Boehringer Ingelheim Pharmaceuticals, Inc., effective November 13, 2025 (SPL set fd638e5e-8032-e7ca-0179-95e96ab5d387), via openFDA; the full label on DailyMed
What does the erythromycin label say about afatinib?
Erythromycin's label (effective August 1, 2024) and its 3 other brand-application labels do not name afatinib 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
| Afatinib | Erythromycin | |
|---|---|---|
| Labeled for | Lung cancer | 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