Captopril agranulocytosis with

Neutropenia/Agranulocytosis Neutropenia (less than 1000/mnr ) with myeloid hypoplasia resulted from captopril use. About half of the neutropenic patients developed systemic or oral cavity infections or other features of agranulocytosis. Neutropenia/agranulocytosis has occurred rarely with enalapril or lisinopril and in 1 patient on quinapril. Data are insufficient to show that moexipril, ramipril, quinapril, benazepril, trandolapril, orfosinopril do not cause agranulocytosis at similar rates. Periodically monitor WBC counts. 

Oates, N.S., R.R. Shah, P.L. Drury, J.R. Idle, and R.L. Smith (1982). Captopril-induced agranulocytosis associated with an impairment of debrisoquine hydroxylation. Br. J. Pharmacol. 14, 60IP. 

The UK manufacturer of captopril also warns that neutropenia and agranulocytosis, resulting in serious infection, have occurred in patients taking captopril and other ACE inhibitors, and that concurrent treatment with allopurinol may be a complicating factor, especially in those with renal impairment. However, the US manufacturer notes that, while renal impairment and a relatively high dose of captopril markedly increases the risk of neutropenia, no association between allopurinol and captopril and neutropenia has appeared in US reports. ... 

Oates NS, Shah RR, Drury PL, Idle JR, Smith RL (1982) Captopril-indueed agranulocytosis associated with an impairment of debrisoquine hydroxyl-ation. Br J Clin Pharmacol 14 601P... 

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