title: Methotrexate pharmacokinetics in patients with rheumatoid arthritis.
abstract: Few studies have evaluated the pharmacokinetics of low dose oral methotrexate (MTX) therapy. MTX pharmacokinetics were studied in 10 patients with classic rheumatoid arthritis (RA) after a single 7.5 mg oral dose. MTX was rapidly absorbed. Peak concentrations varied considerably, ranging from 0.31-0.72 microM. Measurable drug concentration was found in all patients at 24 h after the dose. CL/F-MTX = 145 +/- 52 ml/min/1.73 m2 and elimination half-life was 4.5 +/- 0.89 h. Oral MTX given as a single weekly dose has predictable pharmacokinetics. Further studies to examine what relationship exists, if any, with efficacy and toxicity of MTX in RA must be undertaken.
authors.affiliation: Department of Pharmacy Services, Mary Imogene Bassen Hospital, Cooperstown, NY 13326.
authors.forename: M J
authors.initials: MJ
authors.lastname: Sinnett
authors.forename: G D
authors.initials: GD
authors.lastname: Groff
authors.forename: D A
authors.initials: DA
authors.lastname: Raddatz
authors.forename: W A
authors.initials: WA
authors.lastname: Franck
authors.forename: J S
authors.initials: JS
authors.lastname: Bertino
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000963:Antimetabolites / Q000494:pharmacology; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008727:Methotrexate / Q000493:pharmacokinetics* / Q000627:therapeutic use; D008875:Middle Aged
chemical_list: D000963:Antimetabolites; D008727:Methotrexate