L Arisz

The effect of indomethacin on kidney function and plasma renin activity in man.

125Iothalamate and 131I-hippuran clearances, sodium excretion and plasma renin activity (PRA) before and during indomethacin administration in an oral dose of 3 x 50 mg/day were studied in volunteers with a normal or reduced kidney function, as well on non-sodium-restricted as on sodium-restricted diet. Indomethacin induced a temporary sodium and water retention and a decrease in glomerular filtration rate. It also lowered PRA. The latter phenomenon did not depend on sodium retention and was present within 2 h after an oral dose of 50 mg. The results may be explained by indomethacin-induced inhibition of prostaglandin synthesis.

Treatment of the Nephrotic Syndrome with Indomethacin

In 25 patients with nephrotic syndromes of different origin, indomethacin caused an immediate decrease in glomerular filtration rate (GFR) and urinary protein excretion. This effect of indomethacin on GFR and proteinuria was more pronounced when the renin-angiotensin system was stimulated by a low-sodium diet and 50 mg hydrochlorothiazide daily, and resulted in a significant rise in serum albumin. Withdrawal of indomethacin after 1--3 years of administration was followed by an increase in proteinuria to pretreatment levels in 9 out of 15 patients. A harmful renal effect of long-term indomethacin administration was found to be unlikely. The results suggest that the steroid-resistant nephrotic syndrome can be treated symptomatically by indomethacin.