Herbal Medicine for Cervicogenic Dizziness: A Systematic Review and Meta-Analysis
Abstract Background: Herbal medicines (HMs) have been widely used in the treatment of cervicogenic dizziness (CGD) based on their empirical effectiveness and safety. Herein, we reviewed and evaluated the clinical evidence on the efficacy and safety of HM for CGD. Methods: Among the relevant studies published up to December 2019 in 11 electronic databases, only randomised controlled trials (RCTs) were included. The studies’ methodological quality was assessed using the revised Cochrane risk-of-bias tool for randomised trials, and the strength of evidence for the main findings was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: All 17 included RCTs with 1,797 participants were conducted with six types of modified HM prescriptions and three types of active controls. More than half of the included studies were of low quality because of the high risk of bias due to deviations from the intended intervention. HMs plus active controls were more effective in CGD treatment than active controls alone. HMs plus antivertigo drugs, HMs plus manual therapy, and HMs plus acupuncture therapy were all effective in CGD treatment, with HMs plus antivertigo drugs showing the most reliable effect. All HM prescriptions were effective for specific patterns of CGD when administered with active controls, with Banxia Baizhu Tianma tang and Dingxuan tang demonstrating the most reliable effect. No serious adverse events were reported in all included studies. Conclusions: The current evidence suggests that HMs may enhance the treatment effect on CGD when combined with other treatments without serious adverse events. Further high-quality evidence is needed to draw a definite conclusion.Systematic review registration: PROSPERO (registration number: CRD42020199222), and the Research Registry (Review Registry Unique Identifying Number: reviewregistry1036)