Acne consists of pimples or cysts that appear on the face, back and chest. Most adolescents have some form of acne but many adults also experience acne. Acne is caused by four different activities in the skin. Specifically, excessive oil production by the sebaceous glands, the skin cells shedding too rapidly, increased inflammation in the skin and over production of bacteria. By addressing these causes with a range of therapies most cases of acne can be resolved.