methotrexate sodium · Medicine question

How does methotrexate inhibit DNA synthesis?

iatroX medicinesPublished 8 November 2026

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Methotrexate competitively inhibits dihydrofolate reductase, preventing the reduction of folic acid to tetrahydrofolic acid needed for DNA synthesis and cellular replication.

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Methotrexate 25 mg/ml InjectionHospira UK Ltd · emc · SmPC §5.1 Pharmacodynamic properties · Version 28Document updated 7 September 2026

Sources checked 8 November 2026

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Are any pharmaceutical incompatibilities specified for Methotrexate 2.5 mg Tablets, the Morningside Healthcare Ltd product?Are vials of Methotrexate 25 mg/ml Injection, the Hospira UK Ltd product, single-use, and what should happen to unused contents?By which routes can Hospira UK Ltd's Methotrexate 25 mg/ml Injection be administered?Can methotrexate cause Stevens–Johnson syndrome or toxic epidermal necrolysis?Can methotrexate reduce fertility, and are these effects usually reversible after treatment stops?

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