Objective To investigate metabolic status of nitric oxide(NO)as well as oxidative and lipoperoxidative stress,pathological chain reactions of a series of free radicals,and oxidative and lipoperoxidative damages in patients with acute viral myocarditis(AVM).Methods Using a random paired control design,plasma levels of NO,lipoperoxides(LPO),vitamin C (VC),vitamin E(VE)and β-carotene(β-CAR),erythrocytic level of LPO as well as activities of erythrocytic superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GSH-Px)were investigated by spectrophotometric assays in 60 AVM patients and 60 healthy adult volunteers(HAV).Results Compared with the HAV group,plasma NO,and LPO in plasma and in erythrocyte of the AVM group significantly increased(P = 0.0001),while VC,VE,β-CAR,SOD,CAT and GSH-Px of the AVM group significantly decreased(P = 0.0001).Compared with the AVM group before treatment,plasma NO,and LPO in plasma and in erythrocyte of the AVM group post treatment significantly decreased(P ＜ 0.05),whereas plasma VC,VE and β-CAR as well as erythrocytic SOD,CAT and GSH-Px of the AVM group post treatment significantly increased(P ＜ 0.05).Conclusion The findings in this study suggested that in the AVM patients the metabolism of NO was disturbed,and the pathological chain reactions of a series of free radicals were severely aggravated,thus produced the oxidative damage and lipoperoxidative damages.Therefore,we recommend that antioxidants at suitable dosage,such as VC,VE,β-CAR and others,should be given to AVM patients daily to alleviate potential oxidative and lipoperoxidative damages in their bodies.