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.

Langford Arthritis Res Ther 2003 5:180   doi:10.1186/ar771