Drug interactions between Arava and prednisone

prednisone ↔ leflunomide

Applies to:prednisone and Arava (leflunomide)

MONITOR CLOSELY: The use of leflunomide in combination with other immuno- or myelosuppressive agents may increase the risk of infections. Serious infections including sepsis, as well as opportunistic infections like Pneumocystis jiroveci pneumonia, pulmonary and extrapulmonary tuberculosis, and aspergillosis have been reported with the use of leflunomide, particularly in patients on concomitant hematotoxic therapy. Agents that may be significantly immuno- or myelosuppressive include antineoplastic agents, radiation, zidovudine, linezolid, some antirheumatic agents, high dosages of corticosteroids or adrenocorticotropic agents (greater than 10 mg/day to 1 mg/kg/day, whichever is less, of prednisone or equivalent for more than 2 weeks), and long-term topical or inhaled corticosteroids. There have also been rare reports of pancytopenia, agranulocytosis, and thrombocytopenia in patients receiving leflunomide alone. However, these events occurred more frequently in patients who received concomitant treatment with methotrexate or other hematotoxic agents, or who had recently discontinued these agents. Due to the prolonged elimination half-life of leflunomide's active metabolite, an interaction may occur even when hematotoxic agents are initiated after the discontinuation of leflunomide. Administering a washout procedure with cholestyramine or activated charcoal helps to accelerate elimination of the active metabolite from plasma and reduce the overlap of systemic exposure to these agents.

MANAGEMENT: Close monitoring for the development of infection is recommended if leflunomide is used in patients who have recently received or are receiving other immuno- or myelosuppressive agents, and vice versa. Platelet, white blood cell count, and hemoglobin or hematocrit should be evaluated at baseline and regularly during chronic concomitant therapy. Patients should be advised to contact their physician if they notice signs of infection or experience fever, chills, sore throat, lethargy, body aches, or other flu-like symptoms. If evidence of bone marrow suppression occurs, treatment with leflunomide should be stopped, and cholestyramine or charcoal administered to accelerate elimination of leflunomide's active metabolite from plasma, which otherwise may take up to two years.