RESUMEN
OBJECTIVE: Piper amalago is used in Brazilian folk medicine as diuretic and for the treatment of urinary calculus disease, although no scientific data have been described to support these effects. Thus, this study aims to evaluate the diuretic effects and antilithiatic activity of the ethanolic extract of P. amalago (EEPam). MATERIALS AND METHODS: Ethanolic extracts of P. amalago (125, 250 and 500mg/kg) were orally administered in male Wistar rats (n=5) and urinary excretion was measured at intervals of up to 24h after administration. The antilithiasic effect of EEPam on calcium oxalate urolithiasis crystallization was examined in a turbidimetric model. RESULTS: The oral administration of all doses of EEPam significantly increased urine output after 24h when compared to control group. Moreover, the application of EEPam, induced an inhibitory effect on calcium oxalate crystallization. CONCLUSIONS: According to results, P. amalago extracts showed diuretic and natriuretic activity and antilithiasic effects.