Methotrexate Sodium has 20 known drug interactions based on U.S. FDA drug labeling data. Of these, 1 are contraindicated combinations that should be avoided entirely. 16 are classified as major interactions requiring close medical supervision. Notable interactions include combinations with Nitrous Oxide, Acetazolamide, Acetylsalicylic Acid. Patients taking Methotrexate Sodium should inform their healthcare provider of all current medications — including over-the-counter drugs and supplements — to avoid potentially harmful combinations. Data sourced from OpenFDA and the NIH National Library of Medicine.
- Total
- 20
- Contraindicated
- 1
- Major
- 16
- Moderate
- 3
Contraindicated (1)
- Methotrexate Sodium + Nitrous Oxide— Nitrous oxide anesthesia potentiates methotrexate effects on folate-dependent metabolic pathways, increasing risk of sev…
Major (16)
- Methotrexate Sodium + Acetazolamide— If coadministration cannot be avoided, monitor closely for methotrexate adverse reactions when coadministered with: Oral…
- Methotrexate Sodium + Acetylsalicylic Acid— NSAID that may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions and potentially …
- Methotrexate Sodium + Dapsone— Antifolate drug that may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions and po…
- Methotrexate Sodium + Folic Acid— Decreases clinical effectiveness of methotrexate in patients with neoplastic diseases by competing with reduced folates …
- Methotrexate Sodium + Macrolide Antibiotics— Sulfonamide antibiotics may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions.
- Methotrexate Sodium + Mao Inhibitors— Proton pump inhibitors may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions.
- Methotrexate Sodium + Neomycin— If coadministration cannot be avoided, monitor closely for methotrexate adverse reactions when coadministered with: Oral…
- Methotrexate Sodium + Nonsteroidal Anti-Inflammatory Drugs (Nsaids)— NSAIDs may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions.
- Methotrexate Sodium + Oral Anticoagulants— Highly protein-bound oral anticoagulants may increase methotrexate plasma concentrations, increasing risk of severe adve…
- Methotrexate Sodium + Pemetrexed— Antifolate drug that may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions and po…
- Methotrexate Sodium + Penicillin— If coadministration cannot be avoided, monitor closely for methotrexate adverse reactions when coadministered with: Oral…
- Methotrexate Sodium + Phenytoin— Highly protein-bound drug that may increase methotrexate plasma concentrations, increasing risk of severe adverse reacti…
- Methotrexate Sodium + Probenecid— May increase methotrexate plasma concentrations, increasing risk of severe adverse reactions and potentially reducing cl…
- Methotrexate Sodium + Pyrimethamine— Antifolate drug that may increase methotrexate plasma concentrations, increasing risk of severe adverse reactions and po…
- Methotrexate Sodium + Salicylates— Salicylates may increase methotrexate plasma concentrations and are weak acids that increase methotrexate exposure.
- Methotrexate Sodium + Tetracycline— Highly protein-bound tetracyclines may increase methotrexate plasma concentrations, increasing risk of severe adverse re…
Moderate (3)
- Methotrexate Sodium + Folinic Acid— Decreases clinical effectiveness of methotrexate in neoplastic diseases. Take only as directed by healthcare provider.
- Methotrexate Sodium + Mercaptopurine— May increase methotrexate plasma concentrations, increasing risk of severe adverse reactions. Monitor closely.
- Methotrexate Sodium + Theophylline— Methotrexate increases theophylline plasma concentrations. Monitor theophylline levels and adjust dosage accordingly.