Other names:
Pimples, zits.
Introduction :
A skin disease causing disfiguring pimples, which usually occurs in teenagers.
Types :
Varies from the very occasional spot, to a severely disfiguring form known as acne vulgaris.
Cause :
Pimples are due to a blockage in the outflow of oil (known as sebum) from the thousands of tiny oil (sebaceous) 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 dilated with the 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. The hormonal changes associated with the transition from childhood to adult life is the major aggravating factor in acne. Hormonal variations later in life can also cause changes to the thickness of oil in the skin, and may worsen or improve acne. Pregnancy, menopause and the oral contraceptive pill may all influence pimples in this way. Stress in the patient, either psychological or disease, may cause pimples to worsen. A simple cold, or the onset of exams may see the number of spots increase dramatically. Pressure from spectacles on the bridge of the nose or tight collars, increases in skin humidity from a fringe of hair or nylon clothing, and excessive use of cosmetics that further block the oil duct openings, can all cause deterioration in a person’s acne. If your father or mother had acne, you have a greater risk of developing them. Acne is not infectious.
Incidence :
Usually starts in early teenage years. Acne is generally more severe in teenage males, but starts earlier in females. It may strike later in life too, particularly in women. It affects Caucasians (whites) more than Negroes or Chinese races.
Prevention :
The risk of acne may be reduced by keeping the skin clean, but not by excessive washing or scrubbing.
Course :
