BACKGROUND: Traditional subhibation therapy may easily cause complications, such as respiratory depression and hyportension because of application of chlorpromazine hydrochloride and promethazine in a large dosage.OBJECTIVE: To observe therapeutic effect of modified subhibation therapy (alterative application of five anticonvulsants according to the half life) on status epilepticus in children with severe viral encephalitis (VE).DESIGN: Contrast observation.SETTING: Department of Pediatrics, the First Hospital of Jilin University.PARTICIPANTS: The participants in present study were 96 patients withsevere viral encephalitis including 52 boys and 44 girls who received treatment in the Department of Pediatrics, the First Hospital of Jilin University from February 2000 to March 2006. All children met the diagnostic criteria of Zhufutong Practice Pediatrics (the seventh edition). Two weeks ago, they ever got upper respiratory infection or enteronitis and so on before the onset, spirit abnormal, behavior disorder, limbs act disorder, vomit, headache, convulsion,nervous system masculine signs such as limbs act disord, autonomic nerve damage manifestation, brain nerve palsy, dysreflexia, meningeal irritation sign, cerebrospinal fluid and electroencephalography (EEG)abnormity. All parents provided the confirmed consent. The patients were randomly divided into control group (n =40) and experimental group (n =56).METHODS: Patients in the control group received anticonvulsion, ice compress and routine treatment. The convulsion was treated with five drugs: 0.5 mg/kg wintermin and phenergan, respectively, 100 g/L chlorpromazine hydrochloride (0.5 mL/kg), 5 mg/kg luminal, 0.3 mg/kg ansiolin. When convulsion attacked,those five drugs were given altatively; however, those were not given if the convulsion did not attack.Children in the experimental group were treated with improved subhibation therapy based on routine treatment. The dosages of anticonvulsants were as the same as those in the control group. Based on the half life, every drug was altated every 4 - 6 hours. In addition, anticonvulsants administrated for 2 successive days whether tic attacked or not. Then the hypnotic was removed gradually.MAIN OUTCOME MEASURES: Therapeutic efficacy, time of disappeared clinical symptoms and physical sign, and security of administration.RESULTS: All the 96 patients were involved in the final analysis. ① Total effective rate and reliability:Total effective rate was higher in the treatment groups than the control group ( χ2=5.871 7, P ＜ 0.05). All patients did not have respiratory depression and side effects. ② Time of disappeared clinical symptoms and physical sign: Recovery time of convulsion, fever, headache and vomit was shorter in the treatment group than that in the control group, and there was significant difference (t =17.612 1 - 34.330 7, P ＜ 0.05); in addition, symptoms of status epilepticus were relieved obviously. Meanwhile, recovery time of paralysis,coma and anepia was shorter in the treatment group than that in the control group, and there was significant difference (t =10.660 8 - 24.700 8, P ＜ 0.05).CONCLUSION: Therapeutic effect of improved subhibation therapy on status epilepticus induced by severe viral encephalitis is positively and safer.