Acne [or Acne Vulgaris] is a very common skin problem affecting nearly everyone from puberty onwards. The process that causes acne is complex. In simple terms, it is likely that the oil glands in the skin are too sensitive to the normal levels of male and female hormones in the body. This leads to many events. Too much oil and skin cells are produced forming a plug in the hair follicle, commonly called a blackhead, whitehead or comedo. Also, these follicles become irritated and inflamed, leading to red spots and pus. Bacteria are also involved making irritating enzymes and chemicals. Sometimes the inflammation becomes so severe that large lumps and cysts can form, leading eventually to scarring.