It is permissible for a person to rub themselves in the bath with flour, bran, or other beneficial substances, as there is no excessiveness in what benefits the body; extravagance applies to what wastes water or harms the body. Regarding blood that stains clothing: there is no issue with praying in it if the amount is not greater than a dirham in size. The "dirham-sized" measure weighs approximately one and one-third dirhams. If the blood is less than a full dirham, washing is preferred but not obligatory for prayer. However, if the blood is less than the size of a chickpea, there is no obligation to wash it unless it is menstrual blood. Menstrual blood, urine, and semen, regardless of quantity, must be washed from the clothing, and prayers must be repeated if performed without realizing its presence.
Commentary #5