Table 5.

Cytotoxic medications frequently used in the treatment of Wegener's granulomatosis: strategies to monitor for and prevent toxicity

Medication	Toxicity	Strategy for monitoring or prevention
Cyclophosphamide	Bone marrow suppression	Complete blood counts every 1–2 weeks to maintain the total leukocyte count above 3000/mm3
	Bladder injury	Administer all at once in the morning with a large amount of fluid
		Consideration of MESNA if intermittent dosing is given
	Transitional cell carcinoma of the bladder	Urinalysis every 3–6 months
		Cytology every 6 months
		Cystoscopy in patients with nonglomerular hematuria or abnormal cytology
		If bladder injury present, cystoscopy every 1–2 years
Methotrexate	Bone marrow suppression	Complete blood counts weekly while adjusting dose, and every 4 weeks thereafter
		Consider use of 5–10 mg calcium leucovorin weekly 24 hours after methotrexate, or 1 mg folic acid daily
	Hepatic injury and fibrosis	Monitor liver function tests every 4 weeks
		Liver biopsy based on guidelines established by the American College of Rheumatology
		Alcohol consumption prohibited
	Mucositis	Consider use of 5–10 mg calcium leucovorin weekly 24 hours after methotrexate, or 1 mg folic acid daily
Azathioprine	Bone marrow suppression	Complete blood counts weekly for the first 2 weeks and every 4 weeks thereafter
	Transaminase elevation	Monitor liver function tests every 2 weeks for the first month, every 1–3 months thereafter

MESNA, sodium 2-mercaptoethanesulphonate.