Suan Zao Ren Tang

Purported Benefits, Side Effects & More

Suan Zao Ren Tang

Purported Benefits, Side Effects & More
 Suan Zao Ren Tang

Common Names

  • Suanzaoren
  • Semen Ziziphus Spinosae
  • Ziziphus
  • Sour Jujube Decoction
  • Ziziphus Decoction Formula
  • Tabellae Suanzaoren Tang

For Patients & Caregivers

Tell your healthcare providers about any dietary supplements you’re taking, such as herbs, vitamins, minerals, and natural or home remedies. This will help them manage your care and keep you safe.

What is it?

Suan Zao Ren Tang (SZRT) is a traditional Chinese medicine (TCM) formula. It’s made up of five different herbs. 

What are the potential uses and benefits?

SZRT is used to:

  • Treat insomnia (trouble falling asleep, staying asleep, or waking up too early)
  • Lower anxiety (strong feelings of worry or fear)

Talk with your healthcare providers before taking herbal formulas. They can interact with some medications and affect how they work. For more information, read the “What else do I need to know?” section below.

What are the side effects?

Side effects of SZRT can include:

  • Sleep disruption
  • Dizziness
  • Dry mouth
  • Skin rash on face
  • Urinary urgency
  • Constipation (difficult or infrequent bowel movements)
  • Diarrhea (loose or watery bowel movements)
  • Fatigue (feeling more weak than usual)
  • Lethargy (feeling less energetic)
  • Sweating
What else do I need to know?
  • SZRT may increase the drowsiness effects of some prescription medications so talk with your healthcare provider before taking it.

For Healthcare Professionals

Clinical Summary

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.

Purported Uses and Benefits
  • Insomnia
  • Anxiety
Mechanism of Action

The mechanisms via which SZRT exerts its biological effects are not fully known. Findings from pharmacological studies indicate that its bioactive components including jujubogenin, jujuboside A, and jujuboside B enhance sleep activity by stimulating serotonin and GABA (the major inhibitory neurotransmitter in the central nervous system) receptors (8) (9) (10) (11).

Spinosin, another constituent of SZRT, was found to increase total sleep time and reduce sleep latency in pentobarbital-treated rats (12).


None known.

Adverse Reactions

SZRT may cause side effects that include sleep disruption, dizziness, dry mouth, facial skin rash, urinary urgency, constipation, diarrhea, fatigue, lethargy, and sweating (13) (3) (14) (15) (16).

Herb-Drug Interactions
  • Serotonin reuptake inhibitors: Because of its sedative effects, SZRT may interact with SRIs (17).
  • Monoamine oxidase inhibitors: Due to its sedative effects, SZRT may interact with MAOIs (18).
Dosage (OneMSK Only)
  1. Chen FP, Jong MS, Chen YC, et al. Prescriptions of Chinese Herbal Medicines for Insomnia in Taiwan during 2002. Evid Based Complement Alternat Med. 2011;2011:236341. doi:10.1093/ecam/nep018
  2. Song MF, Chen LQ, Shao QY, Hu LL, Liu WJ, Zhang YH. Efficacy and Safety of Jiawei Suanzaoren Decoction Combined with Lorazepam for Chronic Insomnia: A Parallel-Group Randomized Controlled Trial. Evid Based Complement Alternat Med. 2020;2020:3450989. doi:10.1155/2020/3450989
  3. Chan YY, Chen YH, Yang SN, Lo WY, Lin JG. Clinical Efficacy of Traditional Chinese Medicine, Suan Zao Ren Tang, for Sleep Disturbance during Methadone Maintenance: A Randomized, Double-Blind, Placebo-Controlled Trial. Evid Based Complement Alternat Med. 2015;2015:710895. doi:10.1155/2015/710895
  4. Yeh CH, Arnold CK, Chen YH, Lai JN. Suan zao ren tang as an original treatment for sleep difficulty in climacteric women: a prospective clinical observation. Evid Based Complement Alternat Med. 2011;2011:673813. doi:10.1155/2011/673813
  5. Lee JY, Oh HK, Ryu HS, Yoon SS, Eo W, Yoon SW. Efficacy and Safety of the Traditional Herbal Medicine, Gamiguibi-tang, in Patients With Cancer-Related Sleep Disturbance: A Prospective, Randomized, Wait-List-Controlled, Pilot Study. Integr Cancer Ther. Jun 2018;17(2):524-530. doi:10.1177/1534735417734914
  6. Moon SY, Jerng UM, Kwon OJ, et al. Comparative Effectiveness of Cheonwangbosimdan (Tian Wang Bu Xin Dan) Versus Cognitive-Behavioral Therapy for Insomnia in Cancer Patients: A Randomized, Controlled, Open-Label, Parallel-Group, Pilot Trial. Integr Cancer Ther. Jan-Dec 2020;19:1534735420935643. doi:10.1177/1534735420935643
  7. Yang M, Wang H, Zhang YL, et al. The Herbal Medicine Suanzaoren (Ziziphi Spinosae Semen) for Sleep Quality Improvements: A Systematic Review and Meta-analysis. Integr Cancer Ther. Jan-Dec 2023;22:15347354231162080. doi:10.1177/15347354231162080
  8. Chen CY, Chen YF, Tsai HY. What is the effective component in suanzaoren decoction for curing insomnia? Discovery by virtual screening and molecular dynamic simulation. J Biomol Struct Dyn. Aug 2008;26(1):57-64. doi:10.1080/07391102.2008.10507223
  9. Zhao J, Li SP, Yang FQ, Li P, Wang YT. Simultaneous determination of saponins and fatty acids in Ziziphus jujuba (Suanzaoren) by high performance liquid chromatography-evaporative light scattering detection and pressurized liquid extraction. J Chromatogr A. Mar 10 2006;1108(2):188-94. doi:10.1016/j.chroma.2005.12.104
  10. Chuang G, Mao S, Tam W, Tam G, Tam C. Survey of biological active molecule in the Chinese herbal formula- Suan Zao Ren Tang in treating insomnia. FASEB J. 2009;23:902-913.
  11. Yang B, Zhang A, Sun H, et al. Metabolomic study of insomnia and intervention effects of Suanzaoren decoction using ultra-performance liquid-chromatography/electrospray-ionization synapt high-definition mass spectrometry. J Pharm Biomed Anal. Jan 25 2012;58:113-24. doi:10.1016/j.jpba.2011.09.033
  12. Zhou QH, Zhou XL, Xu MB, et al. Suanzaoren Formulae for Insomnia: Updated Clinical Evidence and Possible Mechanisms. Front Pharmacol. 2018;9:76. doi:10.3389/fphar.2018.00076
  13. Birling Y, Zhu X, Avard N, et al. Zao Ren An Shen capsule for insomnia: a double-blind, randomized, placebo-controlled trial. Sleep. Feb 14 2022;45(2)doi:10.1093/sleep/zsab266
  14. Dai N, Li Y, Sun J, Li F, Xiong H. Self-Designed Ningxin Anshen Formula for Treatment of Post-ischemic Stroke Insomnia: A Randomized Controlled Trial. Front Neurol. 2020;11:537402. doi:10.3389/fneur.2020.537402
  15. Hu LL, Zhang X, Liu WJ, Li M, Zhang YH. Suan zao ren tang in combination with zhi zi chi tang as a treatment protocol for insomniacs with anxiety: a randomized parallel-controlled trial. Evid Based Complement Alternat Med. 2015;2015:913252. doi:10.1155/2015/913252
  16. Scholey A, Benson S, Gibbs A, Perry N, Sarris J, Murray G. Exploring the Effect of Lactium™ and Zizyphus Complex on Sleep Quality: A Double-Blind, Randomized Placebo-Controlled Trial. Nutrients. Feb 17 2017;9(2)doi:10.3390/nu9020154
  17. Shergis JL, Hyde A, Meaklim H, Varma P, Da Costa C, Jackson ML. Medicinal seeds Ziziphus spinosa for insomnia: A randomized, placebo-controlled, cross-over, feasibility clinical trial. Complement Ther Med. Mar 2021;57:102657. doi:10.1016/j.ctim.2020.102657
  18. Yeung WS. Suanzaorentang and serotonin syndrome. J Clin Psychopharmacol. Feb 2008;28(1):113-4. doi:10.1097/JCP.0b013e318161026d
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