Fire dragon cupping therapy for primary dysmenorrhea: a systematic review of available clinical evidence and research gaps

Background Fire Dragon Cupping Therapy (FDCT) combines negative-pressure cupping with controlled thermal stimulation, moving-cup manipulation, and acupoint stimulation, and is increasingly used for primary dysmenorrhea (PD), but its clinical evidence remains uncertain. Objective To identify randomized controlled trials (RCTs) of FDCT for PD and, when no eligible RCTs were found, to map direct non-randomized and indirect contextual evidence. Methods PubMed/MEDLINE, Embase, Cochrane CENTRAL, CNKI, Wanfang, VIP, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform were searched from inception to March 2026. Eligible primary studies were evaluating FDCT alone or as an adjunct in women with PD. Direct non-randomized FDCT studies and indirect studies of related cupping or Traditional Chinese Medicine (TCM) interventions were summarized separately and were not used to estimate FDCT effectiveness. Results Among 890 records, 248 remained after duplicate removal and 80 full-text reports were assessed; no RCT met the primary eligibility criteria. One retrospective comparative study of 112 patients provided the most informative direct evidence: 58 received FDCT plus Shaofu Zhuyu Decoction and 54 received the decoction alone. Favorable post-treatment pain, TCM syndrome, uterine hemodynamic, endothelin-1, and nitric oxide findings were reported (all P < 0.05), but non-randomized allocation and the combined intervention precluded attribution to FDCT. Additional direct or contextual reports were heterogeneous and methodologically limited. Certainty of evidence was very low, and safety reporting was insufficient. Conclusion Current evidence is insufficient to establish the efficacy or safety of FDCT for PD. Adequately powered multicenter RCTs using standardized FDCT protocols, validated outcomes, appropriate comparators, and systematic adverse-event monitoring are required.