U.S. flag

An official website of the United States government

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-.

Cover of InformedHealth.org

InformedHealth.org [Internet].

Show details

Overview: Acne

Last Update: December 5, 2022; Next update: 2025.


Most teenagers will have pimples at some point. Some only have a few small pimples that soon go away again. Others develop persistent and clearly visible acne. This can be very distressing, particularly in puberty.

But there are a number of things that can be done about acne, although patience is needed. This information is about acne in teenagers and young adults, known as “common” acne or acne vulgaris.

At a glance

  • Most teenagers get acne at some point.
  • Some have only a few small pimples and blackheads, while others have a lot of inflamed, pus-filled spots.
  • Acne usually goes away on its own at around the age of 20.
  • There are many medications for the treatment of acne – some are applied to the skin, and others are swallowed.
  • It can take a while for treatment to start working.


The severity of acne can vary quite a bit. Doctors distinguish between mild, moderate and severe forms of acne. There are also inflammatory and non-inflammatory types of acne. Non-inflammatory acne is a milder type, which most people would refer to as “pimples” or “blackheads” rather than “acne.”

Unlike normal pimples, acne develops over a longer period of time and stays longer. It sometimes leaves small red marks or scars behind. “Normal” pimples usually form quickly and then go away again soon afterwards.

  • Mild acne: People with mild acne have comedones (blackheads or whiteheads). These are clogged pores in the skin. The dark color of blackheads has nothing to do with dirt: They look dark because this kind of blackhead is “open” and the skin pigment melanin reacts with oxygen in the air. Whiteheads are closed, and have a white or yellowish head. The more oil builds up, the more likely it is that bacteria will multiply and lead to inflammatory acne. Acne is described as mild if there are only a few acne pimples, or none at all.
  • Moderate acne: People who have moderate acne have noticeably more acne pimples. Inflamed pimples are called “papules” (small bumps) or “pustules” (filled with yellow pus).
  • Severe acne: People who have severe forms of acne have a lot of papules and pustules, as well as nodules on their skin. These nodules are often reddish and painful. The acne may lead to scarring.


During puberty, a child’s body changes to the body of an adult. This change is regulated by hormones such as androgen. Androgen is a male sex hormone which is made in larger amounts during puberty – in girls too. One thing that it does is cause your skin to produce more oil.

The oil that is made in the skin is called sebum, and it is produced in oil glands called sebaceous glands. Sebum protects the skin and helps to keep it moisturized. But if a layer of dead cells blocks the opening of a pore, the sebum can't leave the pore. It builds up in the sebaceous gland, and a blackhead or whitehead develops. If this becomes inflamed, it turns into a pimple (also called a zit or spot). Acne mostly develops on areas of skin that have more oil glands, like the face, chest, back and shoulders.

When teenagers get acne, it‘s usually because the body produces more androgen hormones during puberty. Once their hormone levels have settled down, typically in their early twenties, the acne usually goes away on its own. Not all teenagers have acne, though, so it is thought that genetic factors and the immune system play a role too.

Development of a pimple

Risk factors

There are a lot of theories about what might make acne more likely. Some of these ideas are supported by scientific proof, but many aren't. For instance, people sometimes say that not washing properly gives you acne or makes it worse. There is no scientific proof that this is true. But claims like this can make teenagers feel guilty because they believe they are to blame for their acne.

Some people think that their acne gets worse if they eat particular foods, like chocolate, meat or dairy products. A number of scientific studies have looked into the effect of diet on acne, but they mostly didn't find any link between these two things. Eating a lot of carbohydrates that cause the sugar levels in the blood to rise quickly could possibly play a role. These carbohydrates include very sugary foods, potatoes and white bread. But it's not yet clear whether they really play a role here.

Certain skin care products, such as moisturizing creams or oils that might block skin pores, can make acne worse. That's also true for rubbing your skin too hard or squeezing blackheads.

Some people report that their acne gets worse when they are stressed. Scientific studies also suggest that there is a link here. It is not clear whether there might be a connection between smoking and acne.

Hormones are not only produced by the body. They are sometimes found in medications and other products too. For instance, some hormone treatments can cause acne or make it worse. These include anabolic substances (for building muscles) and medications such as steroids, as well as some drugs for treating epilepsy.


Acne is the most common skin condition in teenagers. Most people will have acne to some degree during puberty. About 15 to 30 out of 100 teenagers have moderate to severe acne. It is much more common in boys than in girls.


Acne often clears up on its own by the age of 20, but some people still have acne when they're over 30. It may leave scars or red marks (brownish marks on darker skin).


Acne can lead to scarring, especially if it is severe. Scars sometimes form when wounds heal. The wounds caused by acne are found in the deeper layers of skin. They heal in very different ways: While some people only have small, flat scars that are hardly noticeable, others have clearly visible indented scars (“pock marks”) on their face. Acne scars can be divided into the following categories:

  • Atrophic scars: If an acne wound doesn't heal properly, not enough connective tissue is made. The scar then forms beneath the surrounding tissue, creating a dent in the skin.
  • Hypertrophic scars: These raised scars can form on your chest, back or shoulders, particularly in people who have severe acne. They develop if too much connective tissue is produced while the wound is healing. This type of acne scar is less common.
  • Keloid scars: Keloid scars also form when too much connective tissue is made. Unlike hypertrophic scars, though, they're bigger than the original inflamed area. This is a very rare type of acne scarring.

Regularly squeezing blackheads and pustules can increase the likelihood of scarring.


People with acne often try out different things to improve the appearance of their skin. There are a lot of different recommendations when it comes to acne, involving things like facial toners, sunlight and specific diets. But not all of them have been proven to work.

Oil-in-water emulsions (lotions) or moisturizing gels (hydrogels) are recommended for skin care. Greasy creams can clog the pores in your skin even more. Soap-free cleansing products that have a similar pH to skin (5.5) are a good idea too. It is important not to overdo it, though, because too much skin care can irritate the skin even more.

There are also a number of medications for acne, to be applied to the skin or swallowed. Some treatment approaches and medications have been proven to effectively reduce acne, while others have not. Examples of effective treatments include benzoyl peroxide, antibiotics and retinoids.

Acne treatment usually requires patience: Most products have to be used for a long time before there is a noticeable improvement. The treatment may take months or even years. Every treatment can have side effects, too.

Everyday life

Many teenagers feel less self-confident during puberty, and may be very negative about themselves and their appearance. This is especially true of teenagers who have acne, who often feel unattractive or might be embarrassed about how they look. Comments people make about their skin condition can be very upsetting. But self-esteem issues and mood swings are a normal part of puberty, even in teenagers who don't have acne. So it would be wrong to blame all puberty-related problems on acne.

The severity of someone’s acne doesn't always directly determine how much it bothers them. Moderate acne can be just as distressing as severe acne.

How people cope with acne varies greatly. Some teenagers are less bothered by it or can deal with it in a more self-confident way, but for others it can be a major problem. Anxiety, depressive thoughts and low self-esteem are generally more common in people who have acne. Teenagers with acne are more likely to become withdrawn and have conflicts with their friends and family.

If having acne makes teenagers feel less self-confident around others, supportive friends and family are particularly important. But they don't want to be constantly reminded of the issue, either. Things like foundation and concealer, sunglasses, long shirts or a haircut with bangs can make it easier to cope with acne in everyday life and feel more confident.

Further information

When people are ill or need medical advice, they usually go to see their pediatrician or family doctor first. In our topic "Health care in Germany" you can read about how to find the right doctor – and our list of questions can help you to prepare for your appointment.


© IQWiG (Institute for Quality and Efficiency in Health Care)
Bookshelf ID: NBK279211


Informed Health Links

Related information

  • PMC
    PubMed Central citations
  • PubMed
    Links to PubMed

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...