Drug reference
methotrexate
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.
Drug class
Oncology (Anti Metabolite)
Mechanism of action
Inhibits dihydrofolic acid reductase; inhibits purine and thymidylic acid synthesis, which in turn interferes with DNA synthesis, repair, and cellular replication; cell cycle specific for S phase of cycle, May inhibit rapid proliferation of epithelial cells in skin.
Common side effects
- Demyelinating encephalopathy
- Hyperuricemia
- Reddening of skin
- Ulcerative stomatitis
Contraindications
- Pregnant women with nonmalignant disease Known hypersensitivity; severe reactions observed
Known interactions (6)
- acitretin + methotrexate Contraindicated
- amoxicillin + methotrexate Major
- ibuprofen + methotrexate Major
- methotrexate + trimethoprim-sulfamethoxazole Major
- Folic Acid + methotrexate Moderate
- methotrexate + Nitrofurantoin Moderate
Related conditions
Frequently asked questions
What drug class is methotrexate?
methotrexate belongs to: Oncology.
How does methotrexate work?
Inhibits dihydrofolic acid reductase; inhibits purine and thymidylic acid synthesis, which in turn interferes with DNA synthesis, repair, and cellular replication; cell cycle specific for S phase of cycle, May inhibit rapid proliferation of epithelial cells in skin.
What are the common side effects of methotrexate?
Demyelinating encephalopathy, Hyperuricemia, Reddening of skin, Ulcerative stomatitis
Which drugs interact with methotrexate?
acitretin, amoxicillin, ibuprofen, trimethoprim-sulfamethoxazole, Folic Acid, Nitrofurantoin
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