Ranitidine and Aspirin: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Jul 11, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ranitidine
No brand names on recordAspirin
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 salicylate plasma levels and decreased antiplatelet effect of aspirin
Interaction Deep Dive
Ranitidine given with aspirin decreased plasma salicylate levels and reduced the inhibition of platelet aggregation normally seen with aspirin alone. The mechanism of action is thought to be a change in the absorption of aspirin1.
Why it happens (mechanism)
Reduced absorption of aspirin
Literature reports
1 report — tap to read
a) Concomitant use of aspirin and ranitidine resulted in lower salicylate blood levels and decreased inhibition of platelet aggregation without reports of adverse effects in a pilot study. Ten healthy male volunteers, mean age 34.7 years, were given aspirin 325 mg/day (days 1 to 4), no drugs for 9 days (washout period), ranitidine 150 mg twice daily (days 14 to 16), and both drugs in the same doses (days 17 to 20). The combination of aspirin and ranitidine exhibited significantly less inhibition of platelet aggregation than aspirin alone, when platelet function was evaluated using adenosine diphosphate or collagen, as well as a Platelet Function Analyzer 100 test. In 6 subjects, mean salicylate levels were 1 mg/dL with ranitidine and aspirin together and 1.6 mg/dL with aspirin alone (p=0.005). In contrast, the platelet aggregation effects of in vitro aspirin and ranitidine together were comparable to that seen with aspirin alone. The suggested mechanism of action is that ranitidine impairs the absorption of aspirin in vivo 1.
Common questions
Can I take Ranitidine and Aspirin together?
Reduced salicylate plasma levels and decreased antiplatelet effect of aspirin Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ranitidine and Aspirin interaction?
It is rated minor. Usually limited clinical impact.
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.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Ranitidine or Aspirin 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)
- Lev EI, Ramabadran RS, Guthikonda S, et al: Effect of ranitidine on the antiplatelet effects of aspirin in healthy human subjects. Am J Cardiol 2007; 99(1):124-128. DOI
Keep reading about Ranitidine
Keep reading about Aspirin
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