Isoprenaline sensitivity and plasma catecholamine concentrations were studied to assess the sympathetic nervous activity in 13 patients with alcoholic cirrhosis and were compared with five controls. In patients with cirrhosis, the dose of isoprenaline required to increase the resting heart rate by 25 beats min-1 (chronotropic dose 25 or CD25) ranged from 2.50 to 34.73 micrograms (median: 4.47 micrograms) and was significantly higher than in controls (range: 0.66 to 2.76 micrograms, median: 1.34 micrograms). In cirrhotic patients, CD25 values were significantly correlated with plasma albumin concentration, resting heart rate and wedged hepatic venous pressure. In patients with cirrhosis, plasma noradrenaline concentrations ranged from 192 to 978 pg ml-1 (median: 444 pg ml-1) and adrenaline concentrations ranged from 5 to 183 pg ml-1 (median: 47 pg ml-1). No correlation was found between noradrenaline or adrenaline concentrations and CD25 values in cirrhotic patients. In conclusion, in patients with cirrhosis, beta-adrenoceptor responsiveness assessed by isoprenaline sensitivity is altered.