Methotrexate and trimethoprim-sulphamethoxazole--a potentially hazardous combination

Clin Exp Dermatol. 1990 Sep;15(5):358-60. doi: 10.1111/j.1365-2230.1990.tb02113.x.


A 74-year-old woman had been treated with methotrexate over 2 years for rheumatoid arthritis. She was admitted to the hospital because of non-healing leg ulcers. After being treated with trimethoprim-sulphamethoxazole for a urinary-tract infection, she developed severe pancytopenia, followed by pneumonia and septic shock. The patient died shortly after. Concomitant treatment with methotrexate and sulphonamides should be strongly discouraged.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Arthritis, Rheumatoid / drug therapy*
  • Drug Synergism
  • Drug Therapy, Combination
  • Female
  • Humans
  • Leg Ulcer / drug therapy
  • Methotrexate / adverse effects*
  • Pancytopenia / chemically induced*
  • Trimethoprim, Sulfamethoxazole Drug Combination / adverse effects*
  • Urinary Tract Infections / drug therapy


  • Trimethoprim, Sulfamethoxazole Drug Combination
  • Methotrexate