Alum is a type of Chinese herb that can be used to treat scabies, eczema and other diseases. Alum can be used both externally and internally. Its external use has the effect of drying dampness and relieving itching (relieving itching by drying dampness), detoxifying and killing insects, and its internal use has the effect of stopping bleeding and diarrhea (stopping bleeding and diarrhea) and expectorating phlegm. Externally, it can be used to treat scabies, eczema and itching, as well as sores and ulcers. Internally, it is used for prolonged diarrhea, blood in the stool, leakage (excessive menstrual flow or dripping), epilepsy and madness. It should be noted that alum is toxic and should not be taken in large quantities for internal use. It should not be taken by those who have weak yin and weak stomach without dampness or heat. Patients with weak constitution should not take this medicine. Adverse reactions are not clear. If the patient is not feeling well, it is recommended to consult a professional physician before using the medicine.