Si Reverse Tang is mainly used to treat cold syncope syndrome of heart and kidney yang decline, and is not usually used to treat spleen and kidney yang deficiency (deficiency of yang qi in the spleen and kidneys). Si Reverse Tang has the effect of returning yang to save the body (by warming yang qi to save fainting, unconsciousness, etc.). It is used to treat cold syncope with Yang deficiency in the heart and kidneys. Symptoms include syncope of the limbs (unconsciousness, accompanied by cold limbs, even to the elbows and knees), coldness (fear of cold), curling up in the bed, weakness of the spirit and desire to sleep, pallor, abdominal pain and discharging of fluid, and vomiting without thirst, etc. If vomiting and refusal of thirst occur after taking the medicine, it is not necessary for the patient to take the medicine. If there is vomiting and refusal after taking the medicine, the liquid can be cooled and taken. This formula is purely pungent and hot products, in the sick hands and feet mild, not for a long time. It should not be taken for a long time. It should not be used by those who have true heat or false cold. If you need to use Si-Yi Tang, it must be used under the guidance of a medical professional.