Major
celecoxib × Methotrexate
Selective COX-2 inhibitor (coxib)×Antimetabolites, folic acid analogues
Mechanism
NSAIDs reduce renal methotrexate clearance (both selective and non-selective COX inhibitors).
Symptoms
Mouth ulcers (mucositis), nausea, diarrhoea, hair loss. Blood counts fall: leukocytes, platelets, erythrocytes. Severe cases: fatal pancytopenia, nephrotoxicity.
Management
At oncologic methotrexate doses, the combination is not prescribed. At low rheumatologic doses, celecoxib is acceptable with full blood count and creatinine monitoring every 1–3 months.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.