General description

Acne is a skin disorder that occurs when hair follicles become covered with oil and dead skin cells. Often, it causes the appearance of comedones, blackheads, or pimples, and it usually appears on the face, forehead, chest, upper back, and shoulders. Acne is more common in teens, although it affects people of all ages.

There are effective treatments, but acne can be persistent. The pimples and rashes heal slowly, and when one begins to disappear, others seem to emerge.

Depending on its severity, acne can cause emotional distress and scarring of the skin. The sooner you start treatment, the lower your risk of these problems.


Frequent acneCommon acneOpen pop-up dialog box

Cystic acne Cystic acneOpen pop-up dialog box

The signs and symptoms of acne vary according to the intensity of the disorder:

  • Closed comedones (clogged pores)
  • Open comedones (open pores)
  • Red and small tender irregularities (papules)
  • Pimples (pustules) which are papules with pus at the tip
  • Large, solid, painful lumps below the skin surface (nodules)
  • Painful, pus-filled lumps below the surface of the skin (cystic lesions)

When to see the doctor

If personal care remedies can’t get rid of acne, see your primary care doctor. The doctor may prescribe stronger medications. If acne persists or is severe, seek treatment from a doctor who specializes in the skin (dermatologist).

In many women, acne can persist for decades, with frequent flare-ups a week before the menstrual period. This type of acne usually goes away without treatment in women who use contraceptives.

In older adults, the sudden onset of severe acne may indicate the presence of a pre-existing condition that requires medical attention.

The Food and Drug Administration warns that some widely used over-the-counter facial cleansers, acne lotions, and other skin products can cause a serious reaction. This type of reaction is not common, so do not confuse it with redness, irritation, or itching when you have applied medications or products.

Seek emergency medical assistance if, after using a skin product, you experience the following:

  • Weakness
  • Difficulty breathing
  • Swelling of the eyes, face, lips, or tongue
  • Stiff throat

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There are four main factors that cause acne:

  • Excessive fat production
  • Obstruction of hair follicles with fat and dead skin cells
  • Bacteria
  • Excessive activity of a type of hormones (androgens)

Acne usually occurs on the face, forehead, chest, upper back, and shoulders, because most of the fat-producing glands (sebaceous glands) are found in these areas of the skin. The hair follicles are connected to the sebaceous glands.

The follicle wall can protrude and produce an open comedone. Or the plug may be open to the surface and then darken, resulting in a closed comedone. A black pimple may look like dirt stuck in your pores. But in reality, the pore is full of bacteria and fat, so it darkens when exposed to air.

Pimples are protruding red dots, with a white center that forms when blocked hair follicles become inflamed or infected with bacteria. Obstructions and inflammation that occur deep in the hair follicles form cyst-like bumps below the surface of the skin. Generally, other pores on the skin, which are the openings of the sweat glands, are not related to acne.

Factors that can worsen acne

These factors can trigger or worsen acne:

  • Hormones Androgens are hormones that increase in the young during puberty and that make the sebaceous glands enlarge and produce more sebum. Hormonal changes related to pregnancy and the use of oral contraceptives can also affect sebum production. And low amounts of androgens circulate in women’s blood that can worsen acne.
  • Certain medications. Examples include drugs that contain corticosteroids, testosterone, or lithium.
  • Diet. Studies indicate that certain dietary factors, including skim milk and carbohydrate-rich foods (such as bread, bagels, and potato chips), can worsen acne. Chocolate was long supposed to worsen acne. A small study of 14 men with acne revealed that eating chocolate was linked to worsening symptoms. More studies are needed to examine why this is happening and to determine if people with acne would benefit from following specific dietary restrictions.
  • Stress. Stress can make acne worse.

Myths about acne

How acne developsHow acne developsOpen pop-up dialog box

These factors have little effect on acne:

  • Foods with high fat content. Eating high-fat foods has little or no incidence on acne. However, working in an environment with a high concentration of fat, such as in a kitchen with fryers, affects acne, because the oil can stick to the skin and clog hair follicles. This further irritates the skin, or favors acne.
  • Hygiene. Dirt from the skin does not cause acne. In fact, rubbing the skin too hard or cleaning it with harsh soaps or chemicals irritates and worsens acne.
  • Cosmetics. Cosmetics don’t always make acne worse, especially if you wear oil-free makeup that doesn’t clog pores (non-comedogenic) and remove makeup regularly. Oil-free cosmetics do not interfere with the effectiveness of acne medications.
  • Adult Acne: Do Natural Hormone Treatments Help?

Risk factor’s

Acne risk factors include the following:

  • Age. Acne can occur in people of any age, but it is more common in teens.
  • Hormonal changes. These changes are common in adolescents, women and girls, and in people taking certain medications, including those containing corticosteroids, androgens, or lithium.
  • Family background. Genetics is involved in acne. If your parents had acne, chances are you have it, too.
  • Greasy or oily substances. You may experience acne when your skin comes in contact with oily lotions and creams, or with grease in a work area like a kitchen with fryers.
  • Friction or pressure on the skin. This can be caused by items such as phones, cell phones, helmets, tight collars, and backpacks.
  • Stress. Stress does not cause acne, but it can empower it if you already have it.