BACKGROUNDDanggui Sini Decoction (DGSND) is a classic prescription for treating primary dysmenorrhea (PD), while, the ameliorating effects of DGSND on PD and its mechanisms are not yet fully understood.PURPOSEThe present study is devoted to investigate the protective effect of DGSND against PD and the possible mechanism from the perspective of metabolomics as well as lipidomics.METHODSDGSND was characterized by UPLC-Q-TOF/MS. The PD rat model was induced by estradiol benzoate and oxytocin, and traditional pharmacology, including writhing times, latency time, biochemical index, organ index, and histopathology were performed to evaluated the efficacy of DGSND on PD. Urine metabolomics strategy combined with functional analysis was adopted to delineate the therapeutic effect of DGSND on PD rats and anchor the crucial pathway, and lipidomics analysis was further performed with the uterine tissue as the research object to elucidate the protective mechanism of DGSND from the perspective of lipid homeostasis. Finally, western blot analysis was used to validate the expression of key metabolic enzymes in lipid metabolism.RESULTSDGSND was effective in ameliorating writhing times, latency time, the value of prostaglandin F2α (PGF2α)/PGE2, uterus index, and morphological changes of PD rats. Metabolic signature of PD rats was primarily characterized by the disturbance of steroid hormone metabolism, amino acid metabolism, and lipid metabolism. Functional analysis revealed the urine biomarkers of PD were most related with lipid abnormality. Further lipidomics analysis indicated DGSND exerted anti-PD effects by remodeling lipid homeostasis, which might be due to the significant correlations between different kinds of lipids, especially the extremely high correlation of phosphatidylethanolamine, phosphatidylcholine, and fatty acids. Moreover, the key metabolic enzymes expression of CK, PLA2, LPCAT3, COX-2, and 5-LOX can be greatly downregulated by DGSND.CONCLUSIONOur findings demonstrated a novel protective mechanism of DGSND against PD by regulating lipid homeostasis.