PIRETANIDE: A NEW DIURETIC

A new diuretic, piretanide (Hoechst), given orally and IV in a dosage of 2 to 3mg in 9 healthy males was an effective

natriuretic largely by inhibiting sodium chloride transport in the ascending portion of the loop of Henle. However, it had additional activity on the proximal tubule. Despite a SUlphonamide structure, none of its effects appeared to be related to inhibition of carbonic anhydrase. Piretanide induced an increase in the percentage of filtered sodium excreted from \.5 % to 14.1 %. Mean peak natriuresis was 15.9 %. Absolute sodium excretion increased by a factor of almost 10. Urinary flow rate almost doubled from 14.6 to 28.7ml/minute. Glomerular mtration rate rose from a mean of 98.4 to I [9.7 m[ I min and there was a similar rise in effective renal plasma flow. 11 enhanced excretion of both acid and base so that urinary pH was unchanged. There was neither phos­phaturia nor side effects. Teredesai. P. and Puschell, J .B : Clinical Pharmacology and Therapeutics 25: 3J I (Mar 1979)

0156-2703/79(0414-0013 $00.50(0 ©AOIS Press INPHARMA 14Apr 1979 13