Efficacy and safety of commercial Chinese polyherbal preparation Liu Shen Wan as adjunctive treatment for herpes zoster and postherpetic neuralgia: a systematic review and meta-analysis

Yajing Li¹ZHANG LE¹Wenya Wang¹Hui Zhao^1,2*Xing Liao^1*

• ¹China Academy of Chinese Medical Sciences Institute of Basic Research in Clinical Medicine, Beijing, China
• ²China Center for Evidence Based Traditional Chinese Medicine, Beijing, China

Background: Liu Shen Wan (LSW), a commercial Chinese polyherbal preparation (CCPP), is frequently utilized as an adjuvant treatment for herpes zoster and postherpetic neuralgia (HZ and PHN). Nevertheless, the clinical efficacy and safety of this treatment remain uncertain. Purpose: This study aims to systematically evaluate the efficacy and safety of Liu Shen Wan as adjunctive treatment in treating HZ/PHN. Methods: A comprehensive search was conducted across PubMed, Web of Science, Embase, Cochrane Library, ClinicalTrials.gov, and four Chinese databases. Eligibility criteria (PICOS) included: (1) patients with HZ/PHN; (2) Liu Shen Wan as adjunctive therapy (experimental group); (3) Conventional treatment only (control group); (4) Primary outcomes: vesicle cessation, scab formation, VAS, PHN incidence; Secondary outcomes: scab shedding time, time to pain resolution, duration of pain persistence, PHN efficacy, adverse reactions; (5) RCTs. Risk of bias was assessed using ROB 2.0, and data synthesis/analysis used RevMan 5.4. No restrictions on language. Results: A total of 21 RCTs (n=1478) were included. Meta-analysis demonstrated that Liu Shen Wan plus conventional treatment significantly outperformed conventional treatment alone in: shortening vesicle cessation time [MD=-1.44, 95%CI (-1.66, -0.93), P<0.00001, I2=70%]; accelerating scab formation [MD=-1.72, 95%CI (-2.09, -1.35), P<0.00001, I2=38%]; reducing scab shedding time [MD=-2.22, 95%CI (-3.64, -0.80), P=0.002, I2=36%]; decreasing time to pain resolution [MD=-2.46, 95%CI (-3.52, -1.39), P<0.00001, I2=0%]; shortening pain persistence duration [MD=-1.97, 95%CI (-2.49, -1.46), P<0.00001, I2=86%]. Additionally, the combination therapy: reduced PHN incidence [RR=0.24, 95%CI (0.10, 0.57), P=0.001, I2=0%]; improved PHN efficacy [OR=6.11, 95%CI (2.91, 12.82), P<0.00001, I2=61%]; lowered adverse reactions [RR=0.60, 95%CI (0.37, 0.96), P=0.03, I2=0%]. No serious drug-related adverse events were reported. Conclusion: Adjunctive Liu Shen Wan therapy demonstrates potential to shorten herpes lesion healing time, improve treatment outcomes, and effectively prevent postherpetic neuralgia compared to conventional treatment alone. It also significantly reduces both the duration of pain and the overall disease course. Nevertheless, limitations in the current evidence base, including study quality and quantity, necessitate further rigorous investigation to confirm the long-term efficacy and safety profile of this combined intervention.