Medically Reviewed on 11/20/2023

What is acne?

Illustration of Comedones: Blackheads and Whitehead
Illustration of Comedones: Blackheads and Whitehead by

Acne (acne vulgaris, common acne) is a disease of the hair follicles of the face, chest, and back that affects almost all teenagers during puberty -- the only exception being members of a few primitive Neolithic tribes living in isolation. It is not caused by bacteria, although bacteria play a role in its development. It is not unusual for some women to develop acne in their mid-to late-20s.

What are the types of acne?

Several types of acne can result from different causes. Types of skin changes in acne include:

  • Blackheads: Open bumps on the skin filled with excess oil and dead skin that look like dark spots as if filled with dirt
  • Whiteheads: Closed bumps filled with oil and dead skin
  • Papules: Small red or pink bumps
  • Pustules: Small pimples containing pus that look like whiteheads surrounded by red rings, which are most likely to scar if picked at
  • Cysts: Pus-filled large pimples that are most likely to scar
  • Nodules: Large and painful solid pimples that are formed deep in your skin
  • Fungal acne: Also known as pityrosporum folliculitis; this type of acne can be itchy and is caused by the accumulation of fungus (yeast) in the hair follicles

Being able to identify different types of acne is crucial when defining skin care goals. Knowing the lingo not only makes it easier for people to choose the right home care products but also makes it helpful when developing a treatment plan. To ensure you're ready to communicate your skin care concerns, learn all about the differences between pustules and papules and the best ways to treat the most common types of acne.

What are the causes of acne?

No one factor causes acne. Acne occurs when sebaceous (oil) glands attached to the hair follicles are stimulated at the time of puberty or due to other hormonal changes. Sebum (oil) is a natural substance that lubricates and protects the skin.

Associated with increased oil production is a change in the manner in which the skin cells mature, predisposing them to plug the follicular pore. The plug can appear as a whitehead if it is covered by a thin layer of skin, or if exposed to the air, the darker exposed portion of the plug is called a "blackhead." The plugged hair follicle gradually enlarges, producing a bump. As the follicle enlarges, the wall may rupture, allowing irritating substances and normal skin bacteria access into the deeper layers of the skin, ultimately producing inflammation. Inflammation near the skin's surface produces a pustule; deeper inflammation results in a papule (pimple); if the inflammation is deeper still, it forms a cyst.

The following may serve as contributing factors to the formation of acne in some individuals:

  • Hormones: An excess production of androgen sex hormones (such as testosterone) during puberty and other hormonal changes, such as during menstruation and pregnancy in women, could cause acne flare-ups.
  • Heredity: If one of your parents had severe acne, your acne will likely be more difficult to control.
  • Pressure: In some patients, pressure from helmets, chin straps, collars, suspenders, and the like can aggravate acne.
  • Drugs: Some medications may cause or worsen acne, such as those containing iodides, bromides, or oral or injected steroids (either the medically prescribed prednisone [Deltasone, Orasone, Prednicen-M, Liquid Pred] or the steroids that bodybuilders or athletes sometimes take). Other drugs that can cause or aggravate acne are anticonvulsant medications and lithium (Eskalith, Lithobid). Most cases of acne, however, are not drug-related.
  • Occupations: In some jobs, exposure to industrial products like cutting oils may produce acne.
  • Cosmetics: Some cosmetics and skincare products are pore-clogging ("comedogenic"). Of the many available brands of skincare products, it is important to read the list of ingredients and choose those that have water listed first or second if one is concerned about acne. These "water-based" products are usually best for those with acne.

Here are some factors that don't usually play a direct role in causing acne:

  • Food: Parents often tell teens to avoid pizza, greasy and fried foods, and junk food. While these foods may not be good for overall health, they don't play an important causal role in acne. Although some recent studies have implicated a high-carbohydrate diet, milk, and pure chocolate in aggravating acne, these findings are far from established.
  • Dirt: Blackheads are oxidized oil, not dirt. Sweat does not cause acne and is produced by entirely separate glands in the skin. On the other hand, excessive washing can dry and irritate the skin.
  • Stress: Some people get so upset by their pimples that they pick at them and make them last longer. Stress, however, does not play much of a direct role in causing acne.

What are the risk factors for acne?

Acne is more common in teenagers aged 16 to 18 years. It has the potential to have severe social and psychological consequences, especially throughout puberty and adolescence.

Acne is inconvenient at any age, but it may be more unpleasant for adults. Unfortunately, acne may appear long into your 30s, 40s, and 50s. It is possible to be acne-free as a teen yet acquire acne later in life.


Acne (Pimples) See more pictures of acne, scars, treatment and other bacterial skin infections See Images

What are the symptoms of acne?

Acne can appear in many forms and may range from mild to severe.

Acne can appear anywhere on the body including the back, shoulders, and chest; however, it most commonly occurs on the face. Acne usually affects teenagers but can even occur in people aged 40-50 years.

Acne vulgaris is typical teenage acne which is characterized by three types of lesions:

  • The comedo or blackhead
  • The inflammatory papule
  • The pustule or pimple

Acne appears on the skin as the following:

  • Occluded pores ("comedones"), also known as blackheads or whiteheads
  • Tender red bumps called pimples or zits
  • Pustules (bumps containing pus)
  • Cysts (the deep pimples and boils of cystic acne)

How do doctors diagnose acne?

Doctors, specifically dermatologists, diagnose acne by conducting a physical examination of the affected area. During their examination, doctors look for the presence of the characteristic signs of acne, such as pimples, blackheads, and whiteheads. The doctor may also ask about the patient's medical history, such as their diet, age, medications, and family history of acne.

Sometimes, doctors perform additional tests to rule out other skin conditions that present with similar symptoms of acne. For instance, they may take a skin scraping to check for fungal or bacterial infections. Some of the other skin conditions that can mimic acne signs and symptoms include the following:

  • Rosacea: This condition is characterized by pimples but not comedones and occurs in the middle third of the face, along with redness, flushing, and superficial blood vessels. It generally affects people in their 30s and 40s and older.
  • Pseudofolliculitis: This is sometimes called "razor bumps" or "razor rash." When cut too close to the skin, growing hairs twist into the skin and produce tender bumps. This is a mechanical problem, and treatment involves shaving less (growing a beard, laser hair removal). Pseudofolliculitis can, of course, occur in patients who have acne, too.
  • Folliculitis: Pimples can occur on other parts of the body, such as the abdomen, buttocks, or legs. These represent not acne but inflamed follicles. If these don't go away on their own, doctors can prescribe oral or external antibiotics, generally not the same ones used for acne.
  • Gram-negative folliculitis: Some patients who have been treated with oral antibiotics for long periods develop pustules filled with bacteria that are resistant to the antibiotics that were previously used. Bacterial culture tests can identify these germs, leading the doctor to prescribe different antibiotics or other forms of treatment.

What are the different grades of acne?

Understanding the grade of acne can help people choose the course of treatment that will be most effective. It will help them select products. It will help them decide if they can treat their acne at home or if they should see their dermatologist.

  • Grade I
    • It is the mildest form of acne. There may be minor pimples, but they will be small and appear only very occasionally and in small numbers (one or two). People will find blackheads, sometimes in great numbers, but there is no swelling.
    • It is commonly seen in early adolescence, especially on the nose and/or forehead.
    • Many adults also experience grade I acne as blackheads on the nose and forehead.
    • It can be successfully treated at home using an over-the-counter product containing salicylic acid.
  • Grade II
    • It is considered moderate acne.
    • There will be blackheads generally in greater numbers. People will start seeing more papules and the formation of pustules in this stage.
    • Blackheads will appear with higher frequency, and general breakout activity will be more obvious. Slight swelling of the skin is now apparent.
    • People may see the acne progress from the nose and forehead to other areas of the face. Acne may start to affect the chest and shoulders, with occasional breakouts on the back, especially in men. Adult women may find higher breakout activity in the cheeks, chin, and jawline area, especially just before and during the menstrual cycle.
    • Grade II acne can still be treated at home using over-the-counter products. In addition to salicylic acid, people should use benzoyl peroxide lotion daily to help kill the bacteria that cause inflamed breakouts.
  • Grade III
    • This type of acne is considered severe.
    • The difference here is the amount of inflammation present. The skin is now obviously reddened and inflamed.
    • Papules and pustules have developed in greater numbers and nodules will be present.
    • Grade III usually involves other body areas such as the neck, chest, shoulders, and/or upper back, as well as the face. The risk of scarring becomes higher because the infection spreads and becomes deeper.
    • A dermatologist should treat acne at this stage. Grade III acne is usually treated with both topical and systemic therapies such as antibiotics available only by prescription.
  • Grade IV
    • It is the most serious form of acne and is often referred to as cystic acne.
    • The skin will display numerous papules, pustules, and nodules, in addition to cysts.
    • There is a pronounced amount of swelling and breakouts are severe. Cystic acne is very painful.
    • Acne of this severity usually extends beyond the face and may affect the entire back, chest, shoulders, and upper arms. The infection is deep and widespread. Nearly all people with cystic acne develop scarring.
    • A dermatologist must treat grade IV acne. Grade IV acne tends to be hard to control and almost always requires powerful systemic medications in addition to topical treatments.

What are the medications and medical treatments used to remove acne?

It's best to consult a primary care physician or dermatologist if an individual is unable to adequately control his or her acne. The goal of treatment should be the prevention of scarring (not a flawless complexion) so that after the condition spontaneously resolves there is no lasting sign of the affliction.

Here are some of the options healthcare providers use to treat acne:

  • Topical (externally applied) antibiotics and antibacterials: These include erythromycin (E-Mycin, Eryc, Ery-Tab, PCE, Pediazole, Ilosone), clindamycin (BenzaClin, Duac), sulfacetamide (Klaron), azelaic acid (Azelex or Finacea), and dapsone (Aczone).
  • Retinoids: Retin-A (tretinoin) has been in use for years, and preparations have become milder and gentler while still maintaining its effectiveness. Newer retinoids include adapalene (Differin) and tazarotene (Tazorac). These medications are especially helpful for unclogging pores. Side effects may include irritation and a mild increase in sensitivity to the sun. Adapalene 0.1% is available without a prescription. With proper sun protection, however, they can be used even during sunny periods. The combination medication is known as Epiduo gel -- which contains the retinoid, adapalene, along with the antibacterial, benzoyl peroxide -- and is applied once a day.
  • Oral medications: Doctors may start antibiotic treatment with tetracycline (Sumycin) or one of the related "cyclines," such as doxycycline (Vibramycin, Oracea, Adoxa, Atridox, and others) and minocycline (Dynacin, Minocin). Other oral antibiotics that are useful for treating acne are cefadroxil (Duricef), amoxicillin (Amoxil, DisperMox, Trimox), and sulfa drugs.
  • Isotretinoin (Accutane) is an oral retinoid medication used to treat severe, resistant, nodular acne that is unresponsive to conventional therapy, including oral antibiotics. However, this medication is very toxic to a developing fetus and women must be on two forms of birth control while taking this drug.
  • Light treatments: Recent years have brought reports of success in treating acne using special lights and similar devices, alone or in conjunction with photosensitizing dyes. It appears that these treatments are safe and can be effective, but it is not clear that their success is lasting. At this point, laser treatment of acne is best thought of as an adjunct to conventional therapy, rather than as a substitute.
  • Chemical peels: Whether the superficial peels (like glycolic acid) are performed by estheticians or deeper ones performed in the doctor's office, chemical peels are of modest, supportive benefit only, and in general, they do not substitute for regular therapy.

What are the possible side effects of acne treatments?

Isotretinoin, also known as Accutane, is one of the most effective oral medications for cystic acne. However, if a patient becomes pregnant while taking isotretinoin, there can be severe developmental problems or deformities in the fetus. It can also cause miscarriage or stillbirth.

Women are usually required to be on two forms of birth control while taking isotretinoin. They are also tested for pregnancy each time they receive another dose. Other side effects of isotretinoin include:

Are there any home remedies for acne?

While it is best to consult a healthcare provider to determine the best treatment for your acne, there are a few home remedies you may try if you wish to avoid taking medications. These home remedies include the following:

  • Cosmetics: Don't be afraid to hide blemishes with flesh-tinted cover-ups or even foundation, as long as it is water-based (which makes it non-comedogenic). There are many quality products available.
  • Facials: While not essential, steaming and "deep-cleaning" pores are useful, both alone and in addition to medical treatment, especially for people with "whiteheads" or "blackheads." Having these pores unclogged by a professional also reduces the temptation to do it oneself.
  • Pore strips: Pharmacies now carry, under a variety of brand names, strips that one applies to the nose, forehead, chin, etc., to "pull out" oil from pores. These are, in effect, do-it-yourself facials. They are inexpensive, safe, and work reasonably well if used properly.
  • Toothpaste: One popular home remedy is to put toothpaste on zits. There is no medical basis for this. The same applies to vinegar.

What is the best skincare routine for acne?

The following are all good basic skin regimens that may help with your acne battle:

  1. Cleanse gently twice daily.
  2. Apply a gel or cream containing 5% benzoyl peroxide; an alternative is sulfur or resorcinol. Use a pad containing 2% salicylic acid to exfoliate each morning.
  3. At night, apply a spot cream containing sulfur to the affected areas.
  4. Use a light skin moisturizer and water-based makeup.

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What is the prognosis for acne?

Treating acne requires patience and perseverance. Any of the treatments listed above may take two or three months to start working (even isotretinoin). Unless there are side effects such as excessive dryness or allergy, it is important to give each regimen or drug enough time to work before giving up on it and moving on to other methods. Using modern methods, doctors can help clear up the skin of just about everyone.

What are the complications of acne?

For some patients, their acne may have gone away but left permanent scarring, known as acne scarring. Fortunately, there are several options available for this complication of acne. Treatment for acne scarring includes surgical procedures to elevate deep, depressed acne scars and laser resurfacing to smooth out shallow acne scars. Newer forms of laser resurfacing ("fractional resurfacing") are less invasive and heal faster than older methods, although results are less complete and the procedures may need to be repeated three or more times. These treatments can help, but they are never completely successful at eliminating acne scars.

5 tips for managing and preventing acne breakouts

Following a few simple tips could help you control your acne symptoms and prevent acne breakouts in the future. These tips include the following:

  1. Lifestyle changes
    • Moderation and regularity are good things, but not everyone can sleep eight hours, eat three healthy meals per day, and drink plenty of water a day.
    • Probably the most useful lifestyle change one can make is to never pick or squeeze pimples. Playing with or popping pimples, no matter how careful and clean one is, nearly always makes bumps stay redder and bumpier longer. People often refer to redness as "scarring," but fortunately, it usually isn't permanent. It's just a mark that takes months to fade if left entirely alone.
  2. Open the pores
    • Occasional visits to an esthetician who is an expert at safely removing blackheads during a facial can be beneficial.
  3. Cleansing and skin care
    • Despite what one might read in popular style and fashion magazines, there is no magic product or regimen that is right for every person and situation.
      • Mild cleansers: Washing once or twice a day with a mild cleansing bar or liquid (for example Dove, Neutrogena, Basis, Purpose, and Cetaphil are all inexpensive and popular) will keep the skin clean and minimize sensitivity and irritation.
      • Exfoliating cleansers and masks: A variety of mild scrubs, exfoliants, and masks can be used. These products may contain salicylic acid in a concentration that makes it a very mild peeling agent. These products remove the outer layer of the skin and thus open pores. Products containing glycolic or alpha hydroxy acids are also gentle skin exfoliants.
      • Retinol: Not to be confused with the prescription medication Retin-A, this derivative of vitamin A can help promote skin peeling.
  4. Reducing bacteria
    • Antibacterial cleansers: The most popular ingredient in over-the-counter antibacterial cleansers is benzoyl peroxide. Benzoyl peroxide causes red and scaly skin irritation in a small number of people, which goes away as soon as one stops using the product. Keep in mind that benzoyl peroxide is a bleach, so do not let products containing benzoyl peroxide come into contact with fabrics, leaving unsightly white spots on colored clothes, shirts, towels, and carpets.
    • Topical (external) applications: Antibacterial cleansers come in the form of gels, creams, and lotions that are applied to the affected area. The active ingredients that kill surface bacteria include benzoyl peroxide, sulfur, and resorcinol. Some brands promoted on the Internet and cable TV (such as ProActiv) are much more costly than identical and sometimes more potent products one can buy in the drugstore.
  5. Reduce excess oil
    • One cannot stop oil glands from producing oil. Even isotretinoin (Accutane, see below) only slows down oil glands for a while; they resume normal activity later. It is possible to get rid of oil on the surface of the skin and reduce the appearance of shine.
      • Use a gentle astringent/toner to wipe away oil. (There are many brands available in pharmacies, as well as from manufacturers of cosmetic lines.)
      • Products containing glycolic acid or one of the other alpha hydroxy acids are also helpful in clearing the skin by causing the superficial layer of the skin to peel (exfoliate).
      • Masks containing sulfur and other ingredients draw out facial oil.
      • Antibacterial pads containing benzoyl peroxide have the additional benefit of helping to wipe away oil.

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Medically Reviewed on 11/20/2023
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Adult Acne: Popular Questions and Answers:

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