Severe pancytopenia in a patient taking low dose methotrexate and probenecid

J Rheumatol. 1991 Apr;18(4):609-10.


A patient with rheumatoid arthritis developed life-threatening pancytopenia resulting from low dose oral methotrexate (MTX) toxicity potentiated by probenecid. Clinically significant drug interactions are not frequently cited as risk factors for MTX hematologic toxicity. As low dose MTX is gaining increasing popularity in rheumatologic practice, these potentially serious interactions should be considered.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Arthritis, Rheumatoid / drug therapy
  • Blood Cell Count / drug effects
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Female
  • Humans
  • Methotrexate / administration & dosage
  • Methotrexate / adverse effects*
  • Methotrexate / therapeutic use
  • Pancytopenia / chemically induced*
  • Pancytopenia / pathology
  • Probenecid / adverse effects*


  • Probenecid
  • Methotrexate