LAUSR

Abstract Background: Despite the rapid advances in medical technology, including endovascular interventions and medications, cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) is still one of the major threats to the lives of patients with SAH. In East Asian countries, various types of herbal medicines have been used to treat cerebrovascular diseases, including SAH. In this review, we aim to evaluate the efficacy and safety of herbal medicines for the prevention and treatment of CVS after SAH. Methods and analysis: Seven databases will be searched for relevant studies from inception to the present date “June 2020”. Only randomized controlled trials (RCTs) that assess the effect and safety of herbal medicines for the prevention and treatment of CVS after SAH will be included. The methodological quality will be evaluated using the Cochrane risk of bias assessment tool. After selecting the appropriate studies, a meta-analysis of the RCTs will be performed. Results: This study will provide a high-quality synthesis of current evidence of herbal medicines for CVS after SAH. Conclusion: Our systematic review will provide evidence to judge whether herbal medicines are effective interventions for patients with CVS after SAH. Ethics and dissemination: Ethical approval is not required, as this study is based on a review of published research. This review will be published in a peer-reviewed journal and disseminated electronically and in print. Trial registration number: Research registry reviewregistry923.