How often you change an adhesive bandage will depend on a few factors. One factor is how much blood or pus is oozing out of the injury. If the bandage soils quickly, you should change it more often. Basic medical guidance recommends changing a bandage a minimum of once per day and no more than four times per day, but it depends on the nature of the injury. In general, try to change the bandage as infrequently as you can without leaving a soiled bandage in place.