0.2 g of potassium permanganate, usually put in about 1 liter of water, is often used for anal diseases, eczema, dermatitis and other injuries. Potassium permanganate solution, often applied to mixed hemorrhoids, anal fistula and other anorectal diseases, as well as eczema, dermatitis and other skin injuries. Different preparation ratios vary in the amount of water used. For a solution with a concentration of 1:5000, 0.2 grams of potassium permanganate generally requires about 1 liter of water. It should be noted that the preparation of potassium permanganate solution should be prepared with warm water to prevent the drug from being ineffective at too high a temperature, which is not conducive to the treatment of the disease; attention should be paid to the concentration of potassium permanganate not to be too high, so as not to cause redness and swelling of the skin and mucous membranes, pain and other injuries. It is recommended that if patients have the need to use it, they should use it under the guidance of a doctor to avoid delaying their condition by self-medication.