Acetylsalicylic Acid and Methotrexate: Drug Interaction Guide
Quick answer: This is a major interaction — avoid combining Acetylsalicylic Acid and Methotrexate unless specifically directed by your doctor.
How Acetylsalicylic Acid interacts with Methotrexate
Salicylates can reduce renal tubular secretion of methotrexate and displace it from plasma proteins, increasing exposure and the risk of marrow suppression, mucositis, and nephrotoxicity.
What you should do
Avoid analgesic or anti-inflammatory doses, particularly with high-dose methotrexate. If low-dose antiplatelet therapy is essential, monitor blood counts, renal function, and signs of methotrexate toxicity.
Key facts
Severity
Major — avoid combination
Mechanism
Salicylates can reduce renal tubular secretion of methotrexate and displace it from plasma proteins, increasing exposure...
Action
Avoid analgesic or anti-inflammatory doses, particularly with high-dose methotrexate. If low-dose antiplatelet therapy i...
Frequently asked questions
Can I take Acetylsalicylic Acid and Methotrexate together?
No — this combination should generally be avoided. Avoid analgesic or anti-inflammatory doses, particularly with high-dose methotrexate. If low-dose antiplatelet therapy is essential, monitor blood counts, renal function, and signs of methotrexate toxicity.
What is the severity of this interaction?
The interaction between Acetylsalicylic Acid and Methotrexate is classified as Major — avoid combination. Salicylates can reduce renal tubular secretion of methotrexate and displace it from plasma proteins, increasing exposure and the risk of marrow suppression, mucositis, and nephrotoxicity.
What should I do if I'm prescribed both?
Avoid analgesic or anti-inflammatory doses, particularly with high-dose methotrexate. If low-dose antiplatelet therapy is essential, monitor blood counts, renal function, and signs of methotrexate toxicity. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.