Mortality due to WG has been significantly decreased by cytotoxic therapy with cyclophosphamide and glucocorticoids. Several studies have addressed different treatment regimens, particularly different maintenance regimens, in order to reduce the potential for cyclophosphamide-induced toxicity. Relapse may be precipitated by the chronic carrier-state of S aureus in the nasopharynx, and is sometimes heralded by rising c-ANCA titers. The treatment of the relapse is determined by the severity of its manifestations. Options for maintenance therapy include methotrexate and azathioprine. The value of therapy with TMSx for maintenance of remission still is uncertain, although its use 3 times a week is recommended for Pneumocystis prophylaxis. The ACR guidelines for monitoring drug toxicity should be followed when treating WG.