The clinical usefulness of assessing hemodynamic response to drug therapy in the prophylaxis of variceal rebleeding is unknown. An open-labeled, uncontrolled pilot trial was performed to evaluate the feasibility and efficacy of using the hemodynamic response to pharmacological treatment to guide therapy in this setting. Fifty patients with acute variceal bleeding underwent a hepatic venous pressure gradient (HVPG) measurement 5 days after the episode. Nadolol and nitrates were initiated, and a second HVPG was measured 15 days later. Responder patients (≥20% decrease in HVPG from baseline) were maintained on drugs, partial responders (≥10% and <20%) had banding ligation added to the drugs, and nonresponders (<10%) received a transjugular intrahepatic portal-systemic shunt (TIPS). Mean follow-up was 22 months. Eight patients (16%) did not receive the second HVPG, 6 of them because of early variceal rebleeding. Of the other 42 patients, 24 were classified as responders (57%); 10 as partial responders (24%), who had banding added; and 8 as nonresponders (19%), who received a TIPS. Patients with cirrhosis of viral etiology compared to alcoholic cirrhosis tended to present more early rebleedings, less response to drugs and needed more TIPS. Variceal rebleeding occurred in 22% of all patients but only in 12% of patients whose hemodynamic response was assessed. The 3 therapeutic groups were not different. In conclusion, using hemodynamic response to pharmacological treatment to guide therapy in secondary prophylaxis to prevent variceal bleeding is feasible and effectively protects patients from rebleeding. In this context, viral cirrhosis seems to present a worse outcome than alcoholic cirrhosis. Copyright © 2006 by the American Association for the Study of Liver Diseases.