Splanchnic and systemic arteriolar vasodilation plays an important role in ascites formation in cirrhosis. Octreotide produces splanchnic vasoconstriction, but the effects on systemic hemodynamics and renal function are controversial. This study evaluated the effect of subcutaneous octreotide administration on systemic hemodynamics, endogenous vasoactive systems, and renal function in cirrhotic patients with ascites. Twenty patients were included: 10 received octreotide 250 microg/12 hr subcutaneously (for five days), and 10 did not. No statistically significant changes were found in mean arterial pressure and cardiac rate. Octreotide induced a statistically significant decrease in plasma renin activity (P < 0.01), plasma aldosterone (P = 0.01) and plasma glucagon (P < 0.05). No significant variations were observed in other systemic vasoactive substances (nitric oxide and prostacyclin). Renal function was not modified in either group. In conclusion, in cirrhotic patients with ascites, subcutaneous octreotide administration decreases plasma glucagon, renin activity, and aldosterone without changing in systemic hemodynamics or renal function.