['To study the effect of using lamivudine to prevent fulminant hepatic failure (FHF) in patients with chronic hepatitis B.', '164 patients were randomly put into a conventional supporting treatment control group and a lamivudine treatment group. In the latter, 82 patients were given lamivudine orally at a dose of 100 mg every day besides the support care which was also given to the control group.', 'The rate of deterioration to chronic severe hepatitis in the lamivudine treatment group was significantly lower than that of the control group (23.2% vs. 46.3%, P < 0.01). 52.6% (20/38) with chronic severe hepatitis in the control group died. Only 26.3% (5/19) in the lamivudine treatment group succumbed to terminal liver disease (P < 0.01). There was a significant difference between the two groups in regards to the complication incidence of gastrointestinal bleeding, infections, hepatic coma, and kidney failure (P < 0.05). In addition, the recovery of liver function and liver fibrosis, and the rates of HBeAg loss and seroconversion in the lamivudine treatment group were better than those in the control group. Furthermore, the serum HBV DNA levels decreased more rapidly and continued to be substantially suppressed in the lamivudine treatment group.'] Does [ Lamivudine administration prevent fulminant hepatic failure in patients with severe chronic hepatitis B ]?