Scars (permanent): People who get acne cysts and nodules often see scars when the acne clears. You can prevent these scars. Be sure to see a dermatologist for treatment if you get acne early — between 8 and 12 years old. If someone in your family had acne cysts and nodules, you also should see a dermatologist if you get acne. Treating acne before cysts and nodules appear can prevent scars.
All acne is not, actually, created equal. This makes perfect sense, seeing as there are so many factors — i.e. hygiene, hormones, and genetics — that can both lead to and exacerbate your breakouts. But knowledge is power, and just knowing that there are different types, and that each kind requires its own plan of attack, puts you ahead of the clear-skin curve. Once you figure out what you're working with, it gets far easier to treat. Here, your ultimate guide to identifying, and then taking down, every type of acne out there, according to dermatologists. Find out how to identify and deal with the different kinds of acne, including blackheads, whiteheads, blind pimples, and cystic zits.
Bowling was right not to worry. Baby acne — or newborn acne, as it’s called to distinguish it from infantile acne, which occurs in older babies — is usually harmless and quite common. “It occurs in about 20 percent of newborns, typically around the time when they’re 3 – to 4-weeks-old,” says Mary Yurko, M.D., PhD, a pediatric dermatologist in Grand Rapids, Michigan.
Salicylic acid and azelaic acid. Azelaic acid is a naturally occurring acid found in whole-grain cereals and animal products. It has antibacterial properties. A 20 percent azelaic acid cream seems to be as effective as many conventional acne treatments when used twice a day for at least four weeks. It's even more effective when used in combination with erythromycin. Prescription azelaic acid (Azelex, Finacea) is an option during pregnancy and while breast-feeding. Side effects include skin discoloration and minor skin irritation.

Acne mechanica is caused by heat, friction, and pressure against the skin, often the result of wearing sports gear such as a helmet or baseball cap. It is sometimes called "sports-induced acne" because it occurs frequently in athletes. Preventive measures include wearing an absorbent material under sports equipment and showering immediately after activity.

Side effects include increased skin photosensitivity, dryness, redness and occasional peeling.[80] Sunscreen use is often advised during treatment, to prevent sunburn. Lower concentrations of benzoyl peroxide are just as effective as higher concentrations in treating acne but are associated with fewer side effects.[79][81] Unlike antibiotics, benzoyl peroxide does not appear to generate bacterial antibiotic resistance.[80]

The recognition and characterization of acne progressed in 1776 when Josef Plenck (an Austrian physician) published a book that proposed the novel concept of classifying skin diseases by their elementary (initial) lesions.[163] In 1808 the English dermatologist Robert Willan refined Plenck's work by providing the first detailed descriptions of several skin disorders using a morphologic terminology that remains in use today.[163] Thomas Bateman continued and expanded on Robert Willan's work as his student and provided the first descriptions and illustrations of acne accepted as accurate by modern dermatologists.[163] Erasmus Wilson, in 1842, was the first to make the distinction between acne vulgaris and rosacea.[164] The first professional medical monograph dedicated entirely to acne was written by Lucius Duncan Bulkley and published in New York in 1885.[165][166]
Pimples are raised red spots with a white center that develop when blocked hair follicles become inflamed or infected with bacteria. Blockages and inflammation that develop deep inside hair follicles produce cystlike lumps beneath the surface of your skin. Other pores in your skin, which are the openings of the sweat glands, aren't usually involved in acne.