The side effects depend on the type of treatment you use. Generally, for topical, over-the-counter creams, you can watch out for stinging, redness, irritation and peeling — these side effects usually don’t go any deeper than the skin. Others, like oral antibiotics or hormonal medications, could come with new sets of complications, so we suggest talking to your doctor before pursuing the treatment.
Antibiotics are an acne treatment used to kill acne-causing bacteria. They may be applied directly on the skin (topical) or taken by mouth (oral). Topical antibiotics kill bacteria in the upper portion of your pores, while oral antibiotics can reach to the lower depths of the pores. Antibiotics used for acne treatment include clindamycin or tetracyclines like doxycycline or minocycline. These antibiotics are the most effective for treating acne because they both kill bacteria and act as anti-inflammatory agents to calm down the skin.
Many skin conditions can mimic acne vulgaris, and these are collectively known as acneiform eruptions.[28] Such conditions include angiofibromas, epidermal cysts, flat warts, folliculitis, keratosis pilaris, milia, perioral dermatitis, and rosacea, among others.[20][72] Age is one factor which may help distinguish between these disorders. Skin disorders such as perioral dermatitis and keratosis pilaris can appear similar to acne but tend to occur more frequently in childhood, whereas rosacea tends to occur more frequently in older adults.[20] Facial redness triggered by heat or the consumption of alcohol or spicy food is suggestive of rosacea.[73] The presence of comedones helps health professionals differentiate acne from skin disorders that are similar in appearance.[8] Chloracne, due to exposure to certain chemicals, may look very similar to acne vulgaris.[74]
Blackheads are a mild form of acne that appear as unsightly, open pores that look darker than the skin surrounding them. They get their dark appearance from a skin pigment called melanin, which oxidizes and turns black when it's exposed to the air. Blackheads aren't caused by dirt, but by sebum (oil) and dead skin cells blocking the pore. If the pore remains open, it becomes a blackhead; if it's completely blocked and closed, it turns into a whitehead.
This inflammatory cascade typically leads to the formation of inflammatory acne lesions, including papules, infected pustules, or nodules.[1] If the inflammatory reaction is severe, the follicle can break into the deeper layers of the dermis and subcutaneous tissue and cause the formation of deep nodules.[1][66][67] Involvement of AP-1 in the aforementioned inflammatory cascade leads to activation of matrix metalloproteinases, which contribute to local tissue destruction and scar formation.[45]
Contrary to popular belief, acne isn't caused by a harmful diet, poor hygiene, or an uncontrolled sex drive. The simple truth is that heredity and hormones are behind most forms of acne. Swearing off chocolate or scrubbing your face 10 times a day won't change your predisposition to this unsightly, sometimes painful, and often embarrassing skin problem.
Every expert we spoke with said the most critical part of combating acne is combating it every day. “The only way to make any medication work is to use it on a daily basis,” says Dr. Green. Aesthetician and Rodan + Fields Consultant, Jessica Fitz Patrick emphasizes that it really comes down to what you can maintain for the long term: “Kits are great because they take out all the guesswork -- you just follow the instructions. But if four steps is going to be too many for you to keep up week after week, you’ll be better off finding one that has fewer treatments.”
Baldwin says squeezing is the best way to get rid of blackheads, but it should be left to a professional if possible. "A good cosmetologist can do an awesome facial," she says. "Pore strips can also help. But both of these are made much easier by starting on a retinoid first. Prescription retinoids soften the pore contents and make the whole process more successful and less painful. With time they will also eradicate the blackheads." The best way to get rid of blackheads for good is with a skin care regimen and the best acne products for clearing the pores. Do not try to pop blackheads or dislodge the blockage with your nails, as your hands may introduce new bacteria to the pores. Instead, see how to get rid of acne fast and prevent blackheads with these acne treatments:
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]

How to Handle It: Think of these as bigger, pissed-off whiteheads. Your best bet, says Zeichner, is to stock up on benzoyl peroxide, which kills the bacteria. A spot treatment like Murad Acne Spot Fast Fix ($22) should do the trick. Also, try not to pop them — as tempting as that may be. Since they're inflamed, they're more likely to scar if you go the DIY route.

Acne appears when a pore in our skin clogs. This clog begins with dead skin cells. Normally, dead skin cells rise to surface of the pore, and the body sheds the cells. When the body starts to make lots of sebum (see-bum), oil that keeps our skin from drying out, the dead skin cells can stick together inside the pore. Instead of rising to the surface, the cells become trapped inside the pore.

A major mechanism of acne-related skin inflammation is mediated by C. acnes's ability to bind and activate a class of immune system receptors known as toll-like receptors (TLRs), especially TLR2 and TLR4.[45][64][65] Activation of TLR2 and TLR4 by C. acnes leads to increased secretion of IL-1α, IL-8, and TNF-α.[45] Release of these inflammatory signals attracts various immune cells to the hair follicle including neutrophils, macrophages, and Th1 cells.[45] IL-1α stimulates increased skin cell activity and reproduction, which in turn fuels comedo development.[45] Furthermore, sebaceous gland cells produce more antimicrobial peptides, such as HBD1 and HBD2, in response to binding of TLR2 and TLR4.[45]
Acne medications work by reducing oil production, speeding up skin cell turnover, fighting bacterial infection or reducing inflammation — which helps prevent scarring. With most prescription acne drugs, you may not see results for four to eight weeks, and your skin may get worse before it gets better. It can take many months or years for your acne to clear up completely.