Dalteparin and Apixaban: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Aug 8, 2026 · Source data updated Jul 11, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Apixaban
Dalteparin
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.
Both of these medicines are blood thinners. Apixaban (Eliquis) and dalteparin (Fragmin) each slow down your blood's ability to clot, just in slightly different ways. When you take them together, that effect adds up, so your risk of bleeding goes higher. That can range from easy bruising to serious bleeding that needs emergency care.
Sometimes doctors do use two blood thinners on purpose for a short time, so this isn't always a mistake. The important thing is that your care team is watching. Watch for signs like unusual bruising, pink or red urine, black stools, nosebleeds that won't stop, or feeling dizzy and weak. If you notice any of these, get help right away.
Additive anticoagulation. Apixaban is a direct factor Xa inhibitor and dalteparin is a low-molecular-weight heparin that also inhibits factor Xa (via antithrombin). Concurrent use produces additive anti-Xa effect and increased bleeding risk.
- Direction: increased anticoagulant effect (neither is a prodrug).
- Magnitude: PD studies with apixaban plus enoxaparin showed a 50 to 60% rise in anti-Xa activity; expect a comparable additive effect with dalteparin.
- Evidence/severity: probable mechanism, major severity.
- Management: avoid overlap unless clinically indicated; monitor for bleeding. Discontinue apixaban if active pathological bleeding occurs. A reversal agent for apixaban anti-Xa activity is available; PCC, aPCC, or rVIIa may be considered. Apixaban PD effect persists at least 24 hours after the last dose.
What happens
An increased risk of bleeding and can cause serious, potentially fatal bleeding
Interaction Deep Dive
Giving apixaban, a factor Xa inhibitor, together with another anticoagulant raises the likelihood of bleeding. Pharmacodynamic interaction studies with apixaban showed that anti-factor Xa activity rose by 50% to 60% when apixaban and enoxaparin were administered concurrently. Apixaban should be stopped if active pathological bleeding develops. A product capable of reversing apixaban's anti-factor Xa activity is on the market. Apixaban's pharmacodynamic effect is anticipated to remain for at least 24 hours following the final dose. Patients should be counseled on the signs and symptoms of blood loss and told to report them without delay or to present to an emergency room. Prothrombin complex concentrate (PCC), activated prothrombin complex concentrate, or recombinant factor VIIa may be considered. If PCCs are given, tracking apixaban's anticoagulant effect through a clotting test (PT, INR, or aPTT) or anti-factor Xa (FXa) activity offers no benefit and is not advised. Absorption of apixaban is reduced by activated oral charcoal, which in turn decreases apixaban exposure1.
Why it happens (mechanism)
Additive anticoagulation
How to manage this interaction
Take both exactly as prescribed and do not stop either one on your own. If your team has you on both, they are usually doing so deliberately and will watch you closely.
- Learn the warning signs of bleeding: unusual or large bruises, blood in urine or stool (or black, tarry stools), coughing or vomiting blood, severe headache, or unusual weakness and dizziness.
- Report any of these right away, or go to an emergency room.
- Your care team may adjust and individualize your doses and monitor you more closely while you are on both.
- Ask your pharmacist or prescriber to confirm how long you should be on both together.
Reassuringly, a reversal agent for apixaban is available if serious bleeding occurs.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In investigations of pharmacodynamic drug interactions involving apixaban, a 50% to 60% rise in anti-factor Xa activity was seen when apixaban and enoxaparin were given together 1.
Common questions
Can I take Dalteparin and Apixaban together?
Apixaban and dalteparin are both blood thinners, and using them together adds up and raises your bleeding risk. Take both as prescribed, watch closely for signs of bleeding, and get emergency help if they occur. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dalteparin and Apixaban 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 is the Dalteparin and Apixaban interaction managed?
Take both exactly as prescribed and do not stop either one on your own. If your team has you on both, they are usually doing so deliberately and will watch you closely. Learn the warning signs of bleeding: unusual or large bruises, blood in urine or stool (or black, tarry stools), coughing or vomiting blood, severe headache, or unusual weakness and dizziness. Report any of these right away, or go… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Dalteparin or Apixaban 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: ELIQUIS(R) oral film coated tablets, apixaban oral film coated tablets. Bristol-Myers Squibb Company (per Dailymed), Princeton, NJ, 2024. DailyMed
Keep reading about Apixaban
Keep reading about Dalteparin
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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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