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Medicines methotrexateQuestion & answer

methotrexate · Medicine question

Which enzyme does methotrexate inhibit to interfere with DNA synthesis?

iatroX medicinesPublished 8 November 2026

The answer

Answer

Methotrexate competitively inhibits dihydrofolate reductase, interfering with DNA synthesis.

Sources for this answer

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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methotrexate

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