Abstract: Objective:To investigate the therapeutic efficacy and safety of phenobarbital in preventing premature newborns from intraventricular hemorrhage (IVH).Methods:Eighty-six premature newborns (≤ 35 weeks gestation and <6 hours post partum) were divided into treatment group (hospitalized in the singular month,n=49) and control group (hospitalized in the even month,n=37).Both groups received the same routine therapy.The patients in the treatment group were administered phenobarbital (20 mg/kg twice via intravenous drip) immediately after admission,followed by a course of 5 days' maintenance dosage (5 mg/kg intravenous drip with 12 hours interval) after 24 hours.The incidences of IVH,severe IVH,respiratory arrest and low response were compared between the two groups.Results:The phenobarbital treatment group had a significantly lower incidence of IVH (20.4%) than the control group (37.8%) (P<0.05).However,there was no difference in the incidence of severe IVH,respiratory arrest or low response between the treatment group (4.1%,34.7% and 24.5%,respectively) and the control group (8.1%,40.5% and 21.6%,respectively).Conclusions:Phenobarbital can effectively and safely prevent the incidence of IVH in premature newborns,and leaves no significant side effects.