title: Aspirin alters methotrexate disposition in rheumatoid arthritis patients.
abstract: Intravenous methotrexate (MTX) (10 mg), either alone or with oral aspirin (ASA) (3,900 mg/day), was administered to 15 patients with rheumatoid arthritis. Systemic and renal clearance of MTX were lower, and the unbound fraction of MTX was higher when patients were also receiving ASA than when taking MTX alone. No acute hematologic, renal, or hepatic toxicity was observed with either treatment. The findings of this study therefore indicate that concomitant aspirin therapy acutely alters the clearance of low-dose MTX in patients with rheumatoid arthritis.
authors.affiliation: Department of Clinical Pharmacy, College of Pharmacy, University of Tennessee, Memphis 38163.
authors.forename: C F
authors.initials: CF
authors.lastname: Stewart
authors.forename: R A
authors.initials: RA
authors.lastname: Fleming
authors.forename: B F
authors.initials: BF
authors.lastname: Germain
authors.forename: M J
authors.initials: MJ
authors.lastname: Seleznick
authors.forename: W E
authors.initials: WE
authors.lastname: Evans
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001798:Blood Proteins / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007668:Kidney / Q000473:pathology; D008297:Male; D008657:Metabolic Clearance Rate / Q000187:drug effects / Q000502:physiology; D008727:Methotrexate / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D008875:Middle Aged; D011485:Protein Binding
chemical_list: D001798:Blood Proteins; D003404:Creatinine; D001241:Aspirin; D008727:Methotrexate