Suan Zao Ren Tang (SZRT) is a traditional Chinese medicine formula with a centuries-long history of use as a treatment for insomnia. Described in the TCM classical text Jin Gui Yao Lue (Essential Prescriptions from the Golden Cabinet), SZRT consists of five herbs: Suan Zao Ren (Sour Jujube seed), Fu Ling (Poria mushroom), Chuan Xiong (Sichuan Lovage root), Zhi Mu (Anemarrhena root) and Gan Cao (Licorice root). SZRT is the most commonly prescribed formula for managing insomnia in Taiwan ⁽¹⁾.

Clinical studies of SZRT have been largely conducted in Asian populations. In a randomized controlled trial of adults with chronic insomnia, adjuvant use of SZRT with Lorazepam led to greater reductions in insomnia severity index with fewer side effects compared to Lorazepam alone. The combination reduced anxiety as well, although there were no significant between-group differences in depression scores. Participants also reported higher physical functioning at 12 weeks ⁽²⁾.

In another study of methadone-maintained patients with disturbed sleep, SZRT affected significant improvements in patient-reported sleep quality and efficiency compared to placebo. However, there were no significant between-group differences in anxiety and depression scores or heroin craving ⁽³⁾.

Additionally, an observational study found SZRT to enhance daytime functioning in climacteric women with poor sleep quality. Of note, women with severe menopause rating scale (MRS) scores had greater improvements compared to those with mild/moderate MRS scores ⁽⁴⁾.

Among cancer patients with insomnia, modified SZRT formulas affected significant reductions in fatigue and insomnia severity index ⁽⁵⁾, and anxiety scores ⁽⁶⁾.

A systematic review/meta-analysis determined that SZRT confers short-term benefits in individuals with sleep disturbance or insomnia. The improvements in sleep quality were significantly greater compared to placebo or waitlist control with comparable effects to benzodiazepine or cognitive behavioral therapy (CBT) ⁽⁷⁾. Future trials are needed to better delineate SZRT’s effects by reducing heterogeneity of trial participants (those with insomnia or inconsistently defined sleep disturbance), to determine its long-term effects, as well as efficacy in diverse populations.