Sodium Bicarbonate and Erlotinib: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Erlotinib
Sodium Bicarbonate
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
The solubility of erlotinib is pH dependent and decreases as pH increases. Concomitant use of erlotinib and drugs that increase the gastric pH, such as antacids, may decrease erlotinib solubility and decrease exposure. When coadministered, separate the dose of erlotinib and antacids by several hours1.
Why it happens (mechanism)
PH related reduction in erlotinib solubility and subsequent reduction in absorption
Common questions
Can I take Sodium Bicarbonate and Erlotinib together?
Reduced erlotinib exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Sodium Bicarbonate and Erlotinib interaction?
It is rated moderate. Can be significant — usually manageable with 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Sodium Bicarbonate 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: TARCEVA(R) oral tablets, erlotinib oral tablets. Genentech USA Inc (per FDA), South San Francisco, CA, 2016. DailyMed
Keep reading about Erlotinib
Keep reading about Sodium Bicarbonate
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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