Acne, spots or pimples can vary from the annual spot, to a severe disease that may cause both skin and psychological scarring. It is generally a curse of teenage years, but it may strike later in life too, particularly in women. Acne is usually more severe in teenage males, but starts earlier in females. Acne affects Caucasians (whites) more than Negroes or Chinese races. The face, upper chest, upper back and neck are most commonly affected.
Acne vulgaris (vulgar acne) is a severe form that almost always results in scarring of the face, back and chest, while acne conglobata affects mainly the buttocks and chest and causes skin abscesses and severe inflammation.
Pimples are due to a blockage in the outflow of oil (known as sebum) from the thousands of tiny oil glands in the skin. This blockage can in turn be caused by dirt (uncommon in our super-clean society), dead skin left behind during the normal regular regeneration of the skin surface, or a thickening and excess production of the oil itself.
Once the opening of the oil duct becomes blocked, the gland becomes inflated with thick oil, then inflamed, and eventually infected. The result is a white head, with the surrounding red area of infection. Eventually this bursts, sometimes leaving a scar.