Heparin and Rivaroxaban: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Rivaroxaban
Heparin
No brand names on record
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
An increased risk of bleeding
Interaction Deep Dive
Avoid concurrent use of rivaroxaban (factor Xa inhibitor, anticoagulant) with other anticoagulants, due to the increased risk of bleeding, unless the benefit outweighs the risk. Promptly evaluate any signs or symptoms of blood loss if patients are treated concomitantly with other anticoagulants. Drug interaction studies of concomitant use of anticoagulants, including rivaroxaban resulted in coadministration of single doses of enoxaparin and rivaroxaban resulted in an additive effect on anti-factor Xa activity. Similarly, concomitant use of single doses of rivaroxaban and warfarin resulted in an additive effect on factor Xa inhibition and PT1.
Why it happens (mechanism)
Additive effect on hemostasis
Literature reports
1 report — tap to read
a) Anticoagulants In a drug interaction study, single doses of enoxaparin (anticoagulant) 40 mg subcutaneous and rivaroxaban (factor Xa inhibitor, anticoagulant) 10 mg given concomitantly resulted in an additive effect on anti-factor Xa activity. In another study, single doses of warfarin (anticoagulant) 15 mg and rivaroxaban (factor Xa inhibitor, anticoagulant) 5 mg resulted in an additive effect on factor Xa inhibition and PT. Neither enoxaparin nor warfarin affected the pharmacokinetics of rivaroxaban 1.
Common questions
Can I take Heparin and Rivaroxaban together?
An increased risk of bleeding Always confirm with your pharmacist or prescriber before making any change.
How serious is the Heparin and Rivaroxaban 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Heparin or Rivaroxaban 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 (1)
- Product Information: XARELTO(R) oral tablets, oral suspension, rivaroxaban oral tablets, oral suspension. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2023. DailyMed
Keep reading about Rivaroxaban
Keep reading about Heparin
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.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist