Pharmacological prevention of variceal bleeding. New developments.

The introduction of pharmacological therapy has been one of the major advances in the treatment of the complications of portal hypertension. Many drugs have been shown to reduce portal hypertension in patients with cirrhosis. However, the most widely used drugs and the only ones for which there is sufficient evidence, are the beta-blockers. These drugs have been, up to now, the only accepted prophylactic therapy for oesophageal variceal bleeding and are also an alternative treatment to sclerotherapy or surgery to prevent variceal rebleeding. A reduction in portal pressure gradient by beta-blockers below 12 mmHg or by more than 20% of baseline values is associated with almost a total protection from oesophageal bleeding. Such a marked response in portal pressure is only achieved in some patients receiving propranolol. New pharmacological approaches with a greater portal pressure reducing effect may improve the beneficial effect of drugs in preventing variceal bleeding. The more promising approach is the combined administration of beta-blockers and isosorbide-5-mononitrate, which has been shown to potentiate the reduction in portal pressure and to be highly effective in initial randomized clinical trials.