Objective:To observe the efficacy of N-acetylcysteine(NAC) injection to 40 patients with chronic hepatitis B.Methods:This is a double blind and randomized clinical trial with parallel control.All of 40 patients were randomly divided into the NAC treatment and placebo group.Each group consisted of 20 patients.The patients in NAC group were treated with NAC injection

once a day with 8 gram for 45 days.The control group was given the placebo.Hepatic function(TBil

PTa

ALT

AST) was tested at 0 day

15 th day

30 th day

45 th day

respectively.Results:Before and 45 days after NAC treatment

the total bilirubin(TBil) were 441.74±125.14 and 128.37±108.26

respectively.In placebo group

TBil were 420.77±154.34 and 181.96±194.30 respectively before and 45 days after treatment.The PTa also was increased.The value were50.00±5.68% and 73.50±21.93% respectively at the start and end of NAC treatment

the increasing rate being 48.78±45.08%.The PTa showed remarkable difference between the two groups.NAC also could decrease the level of alanine aminotransferase(ALT) and aspartic aminotransferase(AST) in serum.Conclusion:NAC can decrease the level of serum TBil

increase the PTa and reduce the time in hospital.NAC showed no adverse effect in the period of treament.It is effective and safe to patients with chronic hepatitis B.