Kinetics of angiotensin-converting enzyme inhibitors in renal failure

Although there is impressive documentation linking severe hypertension to renal insufficiency, corresponding data for mild-to-moderate hypertension are only now starting to emerge. As a result, it is only now becoming evident that a much larger portion of the hypertensive population could be susceptible to drug accumulation owing to renal insufficiency. Angiotensin-converting enzyme (ACE) inhibitor therapy routinely requires dosage adjustment in the instance of renal insufficiency, as all currently marketed ACE inhibitors are renally eliminated. Such dosage adjustments are usually considered a way to minimize side effects and to limit the duration of any induced hypotension. Dosage adjustment is usually considered at creatinine clearance levels between 30 and 60 ml/min. This is somewhat problematic, as physicians generally rely on serum creatinine determinations to assess renal function, and serum creatinine values are notoriously poor predictors of actual creatinine clearance. This is particularly true in the elderly population, where a greater disparity between the serum creatinine and creatinine clearance commonly exists, with moderate renal insufficiency frequently going unrecognized. Thus, the development of other ACE inhibitors eliminated via renal/hepatic routes may prove to be advantageous in that dosage adjustments might not be required in the setting of declining renal function, whether age-related or not. Fosinopril, a new phosphorus-containing ACE inhibitor, is administered as a prodrug and is hydrolyzed to the pharmacologically active diacid, fosinoprilat.(ABSTRACT TRUNCATED AT 250 WORDS)