Effectiveness of adjunctive herbal medicine in the management of post-stroke thalamic pain: a systematic review and meta-analysis.

Post-stroke thalamic pain (PSTP) represents one of the most challenging types of refractory central neuropathic pain. The application of herbal medicine alongside Western medicine (WM) has been proposed as a potential therapeutic option for managing PSTP. Nevertheless, its comprehensive effectiveness and safety have yet to be conclusively established. This study aimed to systematically evaluate the efficacy and safety of herbal medicine combined with WM for the management of PSTP. Eight electronic databases were searched from inception to August 2025 to retrieve randomized controlled trials (RCTs) evaluating combined herbal medicine and WM against WM monotherapy in the management of PSTP. Outcomes included pain intensity measures (VAS, PPI, PRI), anxiety and depression scales (HAMA, SAS, HAMD and SDS), overall treatment effectiveness and adverse events. Sensitivity and subgroup analyses were performed to explore potential sources of heterogeneity. The GRADE framework was used to appraise the strength of evidence for specific results. Trial sequential analysis was carried out with TSA software. The systematic review encompassed 16 trials, incorporating 1,122 participants. The pooled analysis showed that herbal medicine combined with WM was associated with a higher total effective rate than WM alone (RR = 1.38, 95% CI: 1.28-1.49, p < 0.00001). Compared with WM alone, herbal medicine combined with WM significantly reduced VAS score (MD = -1.50, 95% CI: -1.84 - -1.16, p < 0.00001), PPI score (MD = -1.39, 95% CI: -1.55 - -1.22, p < 0.00001), and PRI score (MD = -2.46, 95% CI: -3.24 - -1.69, p < 0.00001). Combination therapy also effectively reduced anxiety (HAMA: MD = -3.10, 95% CI: -3.53 - -2.67, p < 0.00001; SAS: MD = -6.97, 95% CI: -7.49 - -6.46, p < 0.00001) and depression (HAMD: MD = -2.26, 95% CI: -2.72 - -1.80, p < 0.00001; SDS: MD = -7.15, 95% CI: -7.66 - -6.65, p < 0.00001). Regarding safety, herbal medicine combined with WM was not associated with an increased incidence of adverse events compared with WM alone (RR = 0.95, 95% CI: 0.55-1.64, p = 0.86). The certainty of evidence assessed using GRADE ranged from moderate to very low, and TSA provided additional statistical support for the potential benefit of the combined therapy. Evidence from this systematic review indicates that adjunctive herbal medicine combined with WM may have potential benefits in reducing pain, anxiety, and depression, and improving clinical response in patients with PSTP. However, these findings should be interpreted with caution due to methodological limitations and the exclusive inclusion of studies from China. Further rigorous, multicenter, and multinational trials are needed to confirm these findings. The systematic review was registered in PROSPERO (registration number: CRD42024494796).