enalapril and Leukopenia

To date, more than 5000 patients have had experience with enalapril. Over 1000 subjects have been exposed to the drug for more than one year and approximately 600 for over two years. In controlled trials, 2249 subjects, who included normal volunteers and patients with hypertension and congestive heart failure, have received enalapril alone or concomitantly with hydrochlorothiazide or other antihypertensive agents. There have been no deaths attributed to enalapril. The incidence of serious adverse experiences in controlled trials was similar to placebo, and was not higher in the elderly. The incidence of adverse experiences was not dose-related. Drug discontinuation due to adverse experiences was 3.5%, similar to placebo, and approximately half that of control drugs. Serious laboratory adverse experiences were rare. Enalapril attenuated the adverse metabolic effects of hydrochlorothiazide, particularly hypokalaemia. Skin rash occurred in approximately 1.0% of patients. One case of transient taste loss occurred on enalapril, and one on enalapril in combination with hydrochlorothiazide. Neutropenia and agranulocytosis were not encountered. Mean white blood cell counts did not change overall. Most patients (approximately equal to 80%) show no change or an improvement in renal function on enalapril. Discontinuation of concomitant hydrochlorothiazide usually normalized renal function. Enalapril is well tolerated in renal insufficiency. Azotaemia may occur in bilateral renovascular hypertension. Proteinuria was rarely seen and often improved on enalapril. Compassionate use protocols have been available to patients either resistant or intolerant to captopril. Of 68 patients admitted for captopril-related skin rashes, only five recurred on enalapril.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Captopril; Clinical Trials as Topic; Creatinine; Dose-Response Relationship, Drug; Drug Therapy, Combination; Enalapril; Global Health; Heart Failure; Humans; Hydrochlorothiazide; Hypertension; Kidney Diseases; Leukopenia; Skin Diseases; Taste Disorders

Topics: Dipeptides; Enalapril; Hematocrit; Humans; Hypertension; Leukocyte Count; Leukopenia

The mechanisms underlying drug-induced neutropenia are poorly characterized. We have examined the mechanism of suppression of granulocytopoiesis by captopril and penicillamine using human and canine bone marrow cells in an in vitro culture system. Addition of captopril caused no significant change in granulocyte-macrophage colony formation at concentrations up to 30 micrograms/ml. In the presence of CuSO4 (1-3 micrograms/ml), however, captopril caused significant inhibition of colony growth (p less than 0.05). Penicillamine, another agent associated with neutropenia and, like captopril, having a reactive thiol group, also inhibited colony formation in the presence of copper. Chemical congeners of captopril lacking a reactive thiol group and enalaprilic acid, an alternative angiotensin-converting enzyme (ACE) inhibitor, failed to show inhibition, suggesting that the thiol group and not ACE inhibition was responsible. Analysis of day-7 colonies (98% neutrophilic) and day-21 colonies (37% neutrophilic, 30% macrophagic, 27% eosinophilic, and 6% mixed) showed that neutrophil-containing colonies, but not nonneutrophilic colonies were inhibited by the addition of captopril plus copper. Catalase totally reversed the inhibition of colony formation caused by these agents. Direct measurement of oxygen consumption in the presence of captopril showed marked enhancement with the addition of CuSO4 and a 48% reduction in the presence of added catalase. These data indicate that drugs with a reactive thiol group can interact with copper to generate H2O2, which can be toxic to neutrophilic progenitor cells. We postulate that this may be an important mechanism for drug-associated neutropenia and a general mechanism for drug-induced marrow cell injury.

Topics: Animals; Bone Marrow; Captopril; Catalase; Cells, Cultured; Colony-Forming Units Assay; Dogs; Enalapril; Enalaprilat; Granulocytes; Hematopoiesis; Hematopoietic Stem Cells; Humans; Leukopenia; Oxygen Consumption; Penicillamine; Sulfhydryl Compounds

Topics: Aged; Enalapril; Humans; Leukopenia; Liver; Male; Sepsis

Topics: Angiotensin-Converting Enzyme Inhibitors; Dipeptides; Enalapril; Humans; Hypertension; Leukopenia; Male; Middle Aged