Alum is white alum. Alum for the mineral alum stone by processing and refining, also known as alum. Externally, it has the effects of killing insects, drying dampness, detoxifying and relieving itching, and internally, it has the effects of stopping diarrhea, expectorating phlegm, stopping bleeding and opening and closing. Mainly used for treating sores, prolonged diarrhea and dysentery, epistaxis (vomiting blood, nosebleed), scabies, eczema and itching, stroke phlegm (after stroke, the phlegm in the body is overloaded with phlegm evils causing cold limbs, even fainting), epilepsy and so on. Alum with Qingdai, can clear heat, cool blood, dry dampness, applicable to jaundice, more powdered powder. Alum with chebula, can enhance astringent antidiarrheal (through the enhancement of intestinal astringent function to relieve diarrhea) effect, applicable to prolonged diarrhea, dysentery, slippery. Alum with andrographis can enhance the efficacy of astringent sores, insecticide and detoxification, and is used externally for wet sores, scabies, itching and yellow water. Alum taken internally in large quantities can cause hemorrhagic gastritis. Its toxic symptoms are ulceration of the gums, burns of the throat, etc.. Need to strictly control the amount of internal use. Precautions should not be taken in excess. It should not be taken by people with weak stomach. If you need to use the medicine, it is recommended to use it under the guidance of a traditional Chinese medicine practitioner, and unauthorized use of the medicine may cause adverse consequences.