A blister might sound benign to some, but it can be very painful and a real annoyance when you are striving to survive. When you get one, especially on your foot, you want it healed as quickly as possible. Being weighed down by a minor injury is not ideal when every moment counts.
A blood blister is an indication that something not so ideal is going on with your blood and circulatory system. Damage has occurred there which in turn has caused the blister. These are even more painful than conventional blisters and you will want relief like yesterday.
There are several products to consider that treat both blisters and blood blisters. Some are pretty good.