Acne may be mild (few, occasional pimples), moderate (inflammatory papules and pustules), or severe (nodules and cysts).
Mild acne usually causes only whiteheads (closed comedones) and blackheads (open comedones). Whiteheads are white bumps on the skin, comprised of oil and keratin cells, caused by the clogging of pores. Blackheads are pinhead sized dark spots on the skin, caused by small amounts of clogging in pores. The reason that blackheads have a dark color is because the sebum and other material within the pore has been exposed to the oxygen in the air (oxidized). At times, these open and closed comedones may develop into an infection in the skin pore (irritation from the acne bacteria).
Moderate acne suffers can see several to many whiteheads and blackheads (open and closed comedones), along with some bigger papules and nodules. A papule is a raised area of the skin. A nodule is a raised, hardened area of the skin that is larger than a papule.
Severe acne can produce hundreds of whiteheads and blackheads that cover large areas of skin. Cystic lesions are pimples that are large and deep, and may be interconnected. These lesions are often painful and can leave scars on your skin. Sometimes acne needs treatment with stronger medicines or a combination of therapies. Deeper blemishes, such as nodules and cysts, are more likely to leave scars. A dermatologist’s help may be needed to prescribe oral medications to bring cystic acne under control.