What the FDA labels say about taking them together
Erlotinib and lansoprazole
Lansoprazole's FDA label of June 24, 2025 names erlotinib in its drug interactions (prescription label) section; erlotinib's label does not name lansoprazole itself but warns about its class (Proton pump inhibitors (PPIs)). The lansoprazole label: “Lansoprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity.”
Check it at the source: the erlotinib FDA label on DailyMed (effective June 10, 2024, Alembic Pharmaceuticals Limited); the lansoprazole FDA label on DailyMed (effective June 24, 2025, L. Perrigo Company).
What does the erlotinib label say about lansoprazole?
Erlotinib's label does not name lansoprazole itself; it warns about its class (Proton pump inhibitors (PPIs)):
Erlotinib label, drug interactionsDrugs the Increase Gastric pH Co-administration of erlotinib with proton pump inhibitors (e.g., omeprazole) and H-2 receptor antagonists (e.g., ranitidine) decreased erlotinib exposure [see Clinical Pharmacology (12.3)].
Erlotinib label, drug interactionsFor proton pump inhibitors, avoid concomitant use if possible.
Source: FDA drug label (ERLOTINIB HYDROCHLORIDE), Alembic Pharmaceuticals Limited, effective June 10, 2024 (SPL set ab6f3cb3-34a8-4492-a5d7-fb6b055a2d6b), via openFDA; the full label on DailyMed
What does the lansoprazole label say about erlotinib?
Lansoprazole label, drug interactions (prescription label)Clinical Impact: Lansoprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity. Intervention: Mycophenolate mofetil (MMF): Coadministration of PPIs in healthy subjects and in transplant patients receiving MMF has been reported to reduce the exposure to the active metabolite, mycophenolic acid (MPA), possibly due to a decrease in MMF solubility at an increased gastric pH. …
Source: FDA drug label (Prevacid 24 HR), L. Perrigo Company, effective June 24, 2025 (SPL set 205c9c1e-b422-4e86-a4b0-714b608adc19), 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
| Erlotinib | Lansoprazole | |
|---|---|---|
| Labeled for | Lung cancer | Acid reflux and ulcers |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.106 per capsule 30 mg capsule |
| 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