Acne is a most commonly occuring skin imflammation which can affect all the people in their adolescent days. It is an inflammatory disease of the skin, caused by changes in the pilosebaseous units (skin structures consisting of a hair follicle and its associated sebaceous gland). The most common form of acne is known as acne vulgaris, which means common acne.
Excessive secretion of oils from the glands combine with naturally occurring dead skin cells to block the hair follicles. Oil secretions build up beneath the blocked pore, providing a perfect environment for the skin bacteria Propionibacterium acnes to multiply uncontrolled. In response, the skin inflames, producing the visible lesion. The face, chest, back and upper arms are especially exposed.