sulfadiazine and Methotrexate Interactions

Interactions between sulfadiazine(sulfADIAZINE) and Methotrexate (methotrexate)

methotrexate and sulfADIAZINE (Major Drug-Drug)

GENERALLY AVOID: Sulfonamides may decrease the renal clearance of methotrexate. Serum levels of free methotrexate and the risk of bone marrow suppression may be increased. Sulfonamides may also displace methotrexate from plasma protein binding sites, which may further increase serum methotrexate levels and the risk of toxicity. Methotrexate toxicity has also been reported in patients receiving low weekly doses.

MANAGEMENT: This combination should be avoided. If patients do receive methotrexate and a sulfonamide, the complete blood count should be monitored periodically, and the clinician should look for signs and symptoms of anemia, leukopenia, megaloblastosis, and even pancytopenia. Patients should be advised to report possible symptoms of toxicity including nausea, vomiting, diarrhea, stomatitis, sore throat, chills, fever, rash, unusual bruising or bleeding, jaundice, dark urine, swelling of the extremities, or shortness of breath to their physician.