Thanks to its oxidizing and disinfecting properties, potash crystals can effectively treat skin ailments such as eczema. For skin afflictions such as psoriasis and dermatitis, potash crystals help to soothe the resultant blisters. In addition, potash crystal solutions can effectively clean oozing ulcers and abscesses that form on the external body. For all of these uses, you should take a potash crystal bath consisting of a mix of two 400 gram tablets for every eight liters of water. When used in a wrap the concentration is usually much lower, depending on the extent of the soreness. Do not leave the wraps on for more than a half hour.
Potash crystals can be used to treat fungal infections of the foot. For this, you will have to soak your feet in a solution of 100 grams of potash crystals for every 8 liters of water. Doing this three times a day is helpful.
It is not unheard of to use potash in drinking water to oxidize the presence of iron, manganese, harmful bacteria as well as odd smells and tastes. However, this is not considered an at-home procedure.