Also known as furuncles, boils are pockets of pus (a creamy, white substance) on the skin caused by bacteria infecting hair follicles. Cysts—noncancerous sacs of fluid, air, pus, or a soft ...
Boils develop when hair follicles or sweat glands become infected, leading to painful, pus-filled bumps beneath the skin. The warm, moist environment of the armpit creates ideal conditions for ...