During the last 40 years, Danshen injection has been widely used as an adjunctive therapy for angina pectoris in China, but its efficacy is not yet well defined. The objective of this study was to verify the efficacy of Danshen injection as adjunctive therapy in treating angina pectoris.

The major databases including PubMed, Cochrane Library, Sino-Med, Medline, Embase, Google Scholar, China National Knowledge Infrastructure, Wanfang Databases, Chinese Scientific Journal Database, Chinese Biomedical Literature Database and the Chinese Science Citation Database were systematically searched for the published randomised controlled trials (RCTs) on Danshen injection until April 2016. Meta-analysis was conducted on the primary outcomes (i.e., the improvements in symptoms and electrocardiography (ECG)). The quality of the included RCTs was evaluated with the M scoring system (the refined Jadad scale). Based on the quality, year of publication and sample size of RCTs, sensitivity analysis and subgroup analysis were performed in this study.

Ten RCTs, including 944 anginal patients, were identified in this meta-analysis. Compared with using antianginal agents (β-blockers, calcium antagonists, nitrates, etc.) alone, Danshen injection combined with antianginal agents had a better therapeutic effect in symptom improvement (odds ratio [OR], 3.66; 95% confidence interval [CI]: 2.50–5.36) and in ECG improvement (OR, 3.25; 95% CI: 1.74–6.08).

This study showed that Danshen injection as adjunctive therapy seemed to be more effective than antianginal agents alone in treating angina pectoris. However, more evidence is needed to accurately evaluate the efficacy of Danshen injection because of the low methodological quality of the included RCTs.