This study investigates the clinical differentiation and treatment strategies for bipolar disorder （BD） by analyzing the relationship of its core pathomechanisms including qi stagnation， blood stasis， phlegm turbidity， and heat constraint with bile acid metabolism. The imbalance of "yin in form and yang in function" leads to qi stagnation， blood stasis， phlegm turbidity， and heat constraint， which are critical in the pathogenesis and progression of BD. Bile acids regulate neuroinflammation， neural plasticity， and intestinal flora homeostasis through receptor-mediated pathways. It is believed that the physiological functions of bile acids concretely embody the concept of the "liver is yin in form and yang in function" theory. Clinically， prescriptions such as Sini Powder （四逆散） with the function of venting pathogen and resolving constraint， Wendan Decoction （温胆汤） of drying dampness and resolving phlegm， Longdan Xiegan Decoction （龙胆泻肝汤） of clearing liver and draining fire， and Huanglian Ejiao Decoction （黄连阿胶汤） of nourishing yin and blood can be used to nourish liver yin and restore liver yang function. These strategies may improve BD prognosis by modulating bile acid synthesis and metabolism.