Rabeprazole and Erlotinib: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Erlotinib
Rabeprazole
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Reduced erlotinib exposure
Interaction Deep Dive
Concomitant use of erlotinib (pH dependent solubility) and drugs that increase the gastric pH (proton pump inhibitors) decrease erlotinib solubility and exposure1; 3 studies reported significant reductions in erlotinib exposure 234. Erlotinib concentrations during acute treatment of gastric bleed with pantoprazole resulted in therapeutic erlotinib levels during coadministration in a case report 5. Avoid concomitant use; separation of doses may not eliminate the extended affect on the pH of the upper gastrointestinal tract 1.
Why it happens (mechanism)
PH related reduction in erlotinib solubility and subsequent reduction in absorption
Literature reports
4 reports — tap to read
a) Erlotinib with 250 mL of water, given 3 hours after esomeprazole 40 mg resulted in a significant decrease in erlotinib exposure (AUC(24 hours); 47% (95% CI, -57% to -34%)) and decreased Cmax by 56% (95% CI, -64% to -46%) in a pharmacokinetic study of adults with non-small cel lung cancer (N=21); when erlotinib was administered with 250 mL of cow's milk 3.9% fat, exposure to erlotinib was not significantly altered, independent of esomeprazole use 2.
b) Coadministration of erlotinib and proton pump inhibitors (n=12) compared with patients receiving only erlotinib (n=24) resulted in a significant decrease in the plasma-to-dose ratio of erlotinib (0.39 vs 0.51 mcg/[mL x mg x kg]) and a significant increase in erlotinib oral clearance (5.55 vs 3.95 L/hr) in a pharmacokinetic study of patients receiving erlotinib for treatment of non-small cell lung cancer. Proton pump inhibitors included lansoprazole (n=9), omeprazole (n=1), esomeprazole (n=1), or rabeprazole (n=1) 3.
c) Erlotinib trough concentrations were significantly reduced during coadministration of pantoprazole IV infusion, but returned to normal when the dose was reduced and pantoprazole was administered orally in a 46-year-old woman with non-small cell lung cancer requiring acute treatment of gastric bleed and ulcer. On days 16 and 17 of erlotinib 150 mg orally at least 2 hours before or 4 hours after concurrent algeldrate 800 mg/magnesium hydroxide 400 mg 4 times daily, erlotinib trough concentrations were 0.96 and 0.97 mg/L and within expected range (0.7 to 1.7 mg/L). On days 19 and 20 of erlotinib during coadministration of pantoprazole 8 mg/hour IV for 48 hours, trough levels were subtherapeutic at 0.41 and 0.52 mg/L. On days 22 and 23 of erlotinib during coadministration with pantoprazole 40 mg orally twice daily, trough levels returned to expected range at 0.87 and 0.96 mg/L. Administration times or oral pantoprazole and erlotinib were not provided 5.
d) In a pharmacokinetic study (N=24), administration of erlotinib 150 mg 1 hour after omeprazole 40 mg orally once daily resulted in significantly reduced erlotinib AUC by 54% and Cmax by 58% compared with erlotinib alone. Exposure to the major active metabolite, OSI-420, was similarly effected 4.
Common questions
Can I take Rabeprazole and Erlotinib together?
Reduced erlotinib exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Rabeprazole and Erlotinib interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Rabeprazole or Erlotinib need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (5)
- Product Information: TARCEVA(R) oral tablets, erlotinib oral tablets. Genentech USA Inc (per FDA), South San Francisco, CA, 2016. DailyMed
- Veerman GD, Hussaarts KG, Peric R, et al: Influence of cow's milk and esomeprazole on the absorption of erlotinib: a randomized, crossover pharmacokinetic study in lung cancer patients. Clin Pharmacokinet 2021; 60(1):69-77. PubMed
- Ohgami M, Kaburagi T, Kurosawa A, et al: Effects of proton pump inhibitor coadministration on the plasma concentration of erlotinib in patients with non-small cell lung cancer. Ther Drug Monit 2018; 40(6):699-704. PubMed
- Kletzl H, Giraudon M, Ducray PS, et al: Effect of gastric pH on erlotinib pharmacokinetics in healthy individuals: omeprazole and ranitidine. Anticancer Drugs 2015; 26(5):565-572. PubMed
- Ter Heine R, Fanggiday JC, Lankheet NA, et al: Erlotinib and pantoprazole: a relevant interaction or not?. Br J Clin Pharmacol 2010; 70(6):908-911. PubMed
Keep reading about Erlotinib
Keep reading about Rabeprazole
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