No single and decisive cause of this disease has been found so far, but generally, it is related to genetic factors, psychological and social factors, individual character, emotional irritation, infection, and neuroendocrine dysfunction. This disease belongs to "dian kuang" (manic-depressive syndrome) in TCM in accordance with its clinical manifestations. Its causes are congenital defect, anger, fear and fright, or alternate grief and joy, or excessive anxiety. Its pathogenesis is disturbance of turbid phlegm in the heart causing confusion of the mind. Depressive syndrome is attributed to stagnation of phlegm qi while manic syndrome to excessive phlegm fire. In prolonged cases, deficiency of the heart and spleen or hyperactive fire impairing yin may appear.

According to the theory of tradional Chinese medicine, at the initial stage, this disease usually belongs to excess syndrome mostly seen as stagnation of phlegm and qi, phlegm fire disturbing the mind, and blood stasis blocking the heart, while at the late stage, it usually pertains to deficiency syndrome manifested as deficiency of both heart and spleen, and excessive fire impairing yin. The therapeutic principle is to regulate qi and alleviate depression and to activate the mental function. According to the duration of the disease and its pathologic factors, methods such as regulating qi and alleviating depression, clearing heart fire and resolving phlegm, promoting blood circulation and removing blood stasis, invigorating the spleen and nourishing the heart, and nourishing yin and suppressing fire can be used.