Effects of acute administration of nifedipine on glomerular filtration rate and urinary excretion of sodium and uric acid in patients with mild-moderate essential hypertension.

A prospective study was conducted in 25 patients with essential hypertension to study the effects of sublingual administration of nifedipine on some renal functions. Glomerular filtration rate was estimated by radioisotope clearance techniques using Tc-99m diethylene triamine pentaacetic acid (DTPA). The change in urinary excretion of sodium and uric acid were also monitored. A basal estimation of these parameters was followed by repeat studies after lowering the blood pressure to normotensive levels by sublingual administration of nifedipine. It was observed that acute administration of nifedipine does not produce a significant change in the glomerular filtration rate, but causes marked and significant natriuresis and uricosuria.