What is the difference between the efficacy of Wu Pi San and Wu Pi Drink?

There is no difference between the efficacy of Wu Pi San and Wu Pi Drink.
Wu Pi San can also be called Wu Pi Drink, which is mainly composed of Poria Poria, Ginger Pi, Chen Pi, Sang Bai Pi and Dabai Pi, etc. It has the efficacy of strengthening the spleen and promoting the movement of qi, inducing diuresis to reduce edema, and can treat edema, heaviness of the limbs, dysuria, dyspnea (shortness of breath), and other disorders caused by loss of the healthy movement of the spleen (the spleen’s dysfunction of transportation), stagnant qi and water stagnation.
In addition, there are other books on Wu Pi Drink, which has one more flavor of Wu Jia Pi and one less flavor of Sang Bai Pi than this formula, with similar main treatment, but slightly combined with the power of dispelling wind and clearing collaterals.
The adverse effects and contraindications of the above formula are not clear; it is recommended to have a balanced diet and a light diet during the use of the drug. Patients who are not feeling well are advised to consult a doctor in time. If you need to use the above medicines, you should use them under the guidance of a traditional Chinese medicine practitioner, and do not use them on your own.