Wu Pi San can treat the water-stagnation and Qi stagnation of Pi Shui (edema with generalized swelling, low urine output and abdominal distension), which is characterized by swelling of the whole body, heaviness of limbs, distension of the heart and abdomen, shortness of breath and dysuria, dysuria, and edema in pregnancy, with a whitish and greasy texture, and a slow and sedentary pulse. Wu Pi San is composed of Ginger Peel, Sang Bai Peel, Chen Tangerine Peel, Dabao Peel and Poria Peel. In the formula, Poria bark is sweet, light and flat, specializing in skin water and dampness, in order to play the spleen and seepage of dampness, diuresis and edema, for the monarch; abdominal skin to promote gas and flatulence, diuresis and edema; tangerine peel qi and stomach, awakening the spleen and dampness, the same as the subject drug. Ginger skin dispersal of water between the skin to eliminate swelling; Sang Bai Pi purging and lowering lung qi to pass through the waterway, all for the adjuvant. The combination of all the drugs, together with the effect of diuretic swelling, regulate the qi and strengthen the spleen. Avoid spicy, cold and greasy food during the period of taking the drug. It is recommended that under the guidance of the doctor, after the identification of the symptoms of the choice of drugs to regulate the symptoms, after taking the medicine regular follow-up.