ObjectiveTo systematically review the efficacy and safety of dexamethasone in the treatment of viral myocarditis.MethodsThe Cochrane Library, PubMed, EMbase, Biosis Preview, Web of Science, CBM, WanFang Data, VIP, and CNKI databases were electronically searched to collect randomized controlled trials (RCTs) on dexamethasone for patients with viral myocarditis from inception to April 30th, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed using RevMan 5.4 software.ResultsA total of 7 RCTs involving 749 patients were included. The results of meta-analysis showed that the dexamethasone treatment group exhibited an increased efficacy rate (RR=1.26, 95%CI 1.18 to 1.34, P<0.000 01), decreased levels of C-reactive protein (CRP) (MD=?11.49, 95%CI ?19.25 to ?3.72, P=0.004), cardiac troponin I (cTnI) (MD=?26.14, 95%CI ?40.82 to ?11.47, P=0.0005), and creatine kinase MB (CK-MB) (MD=?20.06, 95%CI ?28.35 to ?11.77, P<0.000 01), and a decreased adverse event rate (RR=0.40, 95%CI 0.24 to 0.65, P=0.000 3).ConclusionsCurrent evidence shows that dexamethasone can significantly improve the efficacy rate, reduce the levels of CRP, cTnI, and CK-MB, and reduce the incidence of adverse events in patients with viral myocarditis. Due to the limited quantity and quality of included studies, more high-quality studies are required to verify above conclusions.