Sebum refers to the oily secretion of the sebaceous glands that lubricates the hair and skin. It reaches the skin through the opening of hair follicles. During teenage, the sebaceous glands produce excessive amounts of sebum. The dead skin cells and sebum may get accumulated in the hair follicle, thereby forming a soft plug. The blocked hair follicles can become inflamed due to bacterial action, thereby causing pimples. One can also develop whiteheads, blackheads, nodular or cystic acne, etc. Different Forms of Acne

Pimples	Characteristics
Whitehead	When the soft plug that forms as a result of the accumulation of excess sebum and dead skin cells becomes completely blocked, and the clogged pores closes, the sebum can be seen in the form of white bump or a whitehead.
Blackhead	When the same soft plug is not completely blocked, and remains open at the skin surface, the sebum and dead skin cells oxidize, thereby causing the plug to darken.
Pustules	Pustules are usually red bumps that are tender to touch. These remain inflamed, and have a white or yellow center.
Papules	Similar to pustules, papules indicate infection or inflammation in the hair follicles. They also surface as small, red bumps, which might be tender to touch.
Nodules	In some cases, the excess sebum and dead skin cells start building up deep beneath the surface of hair follicles. When this happens, it causes the formation of lumps. These are called nodular acne. They are large, and seem to occur beneath the surface of the skin. These are usually painful.
Cysts	Probably, these are the most severe and painful. They also form beneath the surface of the skin in the form of lumps. However, cystic acne gets filled with pus, and this is what increases the risk of causing acne scars.
Acne Conglobata	This is a rare and severe form of acne that is known to affect areas such as the back, buttocks, chest, shoulders, upper arms, thighs, and the face. According to experts, it is a combination of pustules and nodules.

Other Types

• Back acne
• Acne Rosacea
• Acne Fulminans
• Gram-negative Folliculitis

Treatment The treatment centers around reducing inflammation and the excess sebum production. It also involves getting rid of the bacterial infection (if any). Also, speeding up the skin cell turnover is one of the goals of the treatment. Over-the-counter medications are good only for dealing with mild acne. For severe form of acne, doctors recommend the use of prescription-strength topical lotions. These products contain vitamin A as one of their active ingredients. They basically prevent the formation of the soft plug. The use of antibiotics might be recommended in some cases. Affected individuals might have to follow a course of topical and oral antibiotics. For cysts, stronger drugs are prescribed. Other treatment methods include the use of oral contraceptives, laser and light therapy, and cosmetic procedures. Besides taking drugs, affected individuals should also follow certain self-care measures. It's best to wash the pimple-affected areas with a gentle cleanser. Drink plenty of water, and follow a proper skin-care regimen. Most importantly, leave your pimples alone and do not squeeze them. Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a dermatologist.