methotrexate sodium

The sodium salt of methotrexate, an antimetabolite with antineoplastic and immunomodulating properties. Methotrexate binds to and inhibits the enzyme dihydrofolate reductase, resulting in inhibition of purine nucleotide and thymidylate synthesis and, subsequently, inhibition of DNA and RNA syntheses. Methotrexate also exhibits potent immunosuppressant properties.