Drug interactions
Acetylsalicylic acid + Dalteparin
Severity: Major
Acetylsalicylic acid and Dalteparin: major interaction.
Last updated Sources: US FDA label
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Aspirin adds to the anticoagulant effect of dalteparin and increases the risk of bleeding, including at injection sites and in the GI tract. The combination is used intentionally in some cardiac conditions but needs vigilance.
What this interaction means in plain words
Acetylsalicylic acid and Dalteparin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Acetylsalicylic acid belongs to Musculoskeletal; Dalteparin belongs to Cardiovascular.
Why it happens
Additive hemostatic impairment: antithrombin-mediated factor Xa inhibition by dalteparin plus platelet inhibition and mucosal injury by aspirin.
What to do
Use together only when clearly indicated, with aspirin at the lowest effective dose. Monitor for bleeding and check hemoglobin and platelet counts regularly.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Acetylsalicylic acid
- Acetylsalicylic acid + Ketorolac Contraindicated
- Acetylsalicylic acid + Ketorolac intranasal Contraindicated
- Abciximab + Acetylsalicylic acid Major
- Acemetacin + Acetylsalicylic acid Major
- Acetazolamide + Acetylsalicylic acid Major
- Acetylsalicylic acid + Alteplase Major
Other interactions of Dalteparin
- Dalteparin + Defibrotide Contraindicated
- Dalteparin + Ketorolac Contraindicated
- Dalteparin + Mifepristone Contraindicated
- Abciximab + Dalteparin Major
- Acalabrutinib + Dalteparin Major
- Aceclofenac + Dalteparin Major
Frequently asked questions
Can I take Acetylsalicylic acid with Dalteparin?
MediHelp rates the interaction as major. Acetylsalicylic acid and Dalteparin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Aspirin adds to the anticoagulant effect of dalteparin and increases the risk of bleeding, including at injection sites and in the GI tract. The combination is used intentionally in some cardiac conditions but needs vigilance.
How serious is the interaction between Acetylsalicylic acid and Dalteparin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use together only when clearly indicated, with aspirin at the lowest effective dose. Monitor for bleeding and check hemoglobin and platelet counts regularly.
What other medicines interact with Acetylsalicylic acid?
MediHelp also lists interactions of Acetylsalicylic acid with, for example, Ketorolac, Ketorolac intranasal, Abciximab. The full list is on the Acetylsalicylic acid page.
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