title: Metabolism of methotrexate in man after high and conventional doses.
abstract: Methotrexate has been found to be extensively metabolized to 7-hydroxymethotrexate in patients receiving conventional doses (less than 10 mg/kg) and high doses (greater than 10 mg/kg). Twelve hours after administration, plasma levels of this metabolite in several patients treated with low doses exceeded those of methotrexate. No 7-hydroxymethotrexate was found in CSF after CNS administration of methotrexate; however, small amounts of the metabolite was found in the CSF after intravenous high dose infusion. We conclude that methotrexate is significantly metabolized in man at all doses used clinically.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006207:Half-Life; D006801:Humans; D008727:Methotrexate / Q000008:administration & dosage / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*
chemical_list: D008727:Methotrexate