The development of varices is a major complication of cirrhosis, and variceal haemorrhage has a high mortality. There have been major advances in the primary and secondary prevention of variceal haemorrhage over the last 20 years involving endoscopic, radiological and pharmacological approaches. This review concentrates principally on drug therapy, particularly on the numerous haemodynamic studies. Many of these drugs have not been studied in clinical trials, but provide data about the underlying pathogenesis of portal hypertension. Also covered in this review are the randomized controlled trials and meta-analyses that involve a large number of patients. These trials involve relatively few drugs such as non-selective beta-blockers and nitrates. Correlations between haemodynamic and clinical parameters are discussed. Despite the recent increase in the use of alternative endoscopic therapies, an effective and well tolerated drug remains a clinically important research goal.