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.