The Efficacy and Safety of Zaoren Anshen Capsule in Combination with Zolpidem for Insomnia: A Multicentre, Randomized, Double-Blinded, Placebo-Controlled Trial

PURPOSE: Insomnia is the most common sleep disorder with high rate of prevalence, persistence, and leads to negative consequences. The mainstays of insomnia treatment have limitations due to either the side effects of hypnotics or limited accessibility to cognitive behavioral therapy. This study aims to compare the efficacy and safety of the traditional Chinese medicine (TCM) Zaoren Anshen capsule alone or as an adjunct treatment with different doses of the nonbenzodiazepine medication zolpidem tartrate in treating insomnia. METHOD: This randomized, double-blind, multicentre placebo control trial was conducted in 131 patients with chronic insomnia. The patients were randomly assigned to one of the following four regimen groups: Group ZA + Z5 : Zaoren Anshen capsule and 5 mg zolpidem tartrate (n = 32); Group Z5: 5 mg zolpidem tartrate and placebo capsule (n = 35); Group Z10 : 10 mg zolpidem tartrate and placebo capsule (n = 32); Group ZA : Zaoren Anshen capsule and placebo pill (n = 32). The drugs were administered for 4 weeks. All patients were evaluated by the Insomnia Severity Index (ISI) at 0, 2, 4, 5, and 6 weeks, and adverse events were recorded. RESULT: There are significant differences in the comparison between the four groups at each treatment stage (P < 0.05). Repeated measurement analysis of variance (ANOVA) of ISI scores in each treatment stage of the four groups exhibits significant differences in time effect, intergroup effect, and interaction effect (P < 0.05). After four weeks of drug administration, the treatment efficacy is similar in Groups ZA + Z5 and Z10 (93%) and in Groups Z5 and ZA (62% and 65%, respectively). Groups ZA + Z5 and Z10 present significantly lower ISI scores compared with Groups Z5 and ZA (P < 0.05), which indicates better treatment response of Groups ZA + Z5 and Z10. No significant difference was observed in the incidence of adverse events between the groups. CONCLUSION: Zaoren Anshen capsule can effectively treat insomnia disorder either alone or in combination with zolpidem tartrate. A preferred combination of TCM Zaoren Anshen capsule with zolpidem can provide a magnified therapeutic efficacy with fewer side effects than zolpidem-only management, clinical trial registration number: Chinese Clinical Trial Registry ChiCTR-IPR-1600969.