Acne is a common, inflammatory, and recurrent condition of the pilosebaceous follicles of the skin that gives rise to the appearance of comedones or pimples that evolve into nodules or cysts. This process affects a large number of adolescents of both sexes.

Between 10 to 20% of people with acne may continue to have skin lesions into adulthood, which can adversely affect their body image and self-esteem.

Acne affects the areas with the highest concentration of sebaceous glands, such as the face, chest, and back. The age of greatest incidence is between 14-16 years in women and 16-19 years in men.


Acne occurs because the skin’s pores become clogged with dead cells and oil, giving rise to comedones. This facilitates colonization (infection) by bacteria (Propionibacterium acnes), leading to an area of ​​inflammation and redness.

Acne generally begins during puberty because hormonal changes make the skin oilier.


The first acne lesions are comedones or pimples. Comedones can be black (open) or white (closed). These lesions usually appear on the nose, chin, and center of the forehead. White pimples swell more often than black pimples. Larger cysts are deeper blockages and are often found on the cheeks, around the nose, and on the back.

When there is added inflammation, there are usually larger lesions, including nodules, with pus inside (pustules) that can produce scars.


Acne is a clinical diagnosis; it does not require any special tests.


There is a greater tendency for children of parents with acne to also develop acne.


Acne is not a contagious disease.


Acne can be prevented if the following tips are followed:

  • Avoid oil-based cosmetics because they increase the fat content of the skin and worsen acne.
  • Limit how often you wash your face to twice daily. The face should be washed gently with warm water and neutral soap without rubbing the skin.
  • Use a moisturizer, ideally, ones labelled “non-comedogenic.”


Acne generally lasts between 3 and 5 years, although some people may have it for 15 to 20 years. Only early treatment with oral isotretinoin can change the natural history of acne.


There are six primary categories of acne-related spots:

  • Blackheads – these are little, black, or yellowish lumps that form on the skin. They usually are not clogged with dirt; rather, the color of the interior hair follicle generates the black color.
  • Whiteheads – similar in look to blackheads, whiteheads can be stiffer and do not pop when pushed.
  • Papules – these are little red pimples that can be uncomfortable or painful. Unlike whiteheads, pimples do not have a visible center of pus, and unlike blackheads, pimples do not appear to have enlarged pores. When the acne breaks and the bacteria spreads into the skin tissue, it can cause irritation and form pimples.
  • Pustules – these are larger, slightly raised bumps with a well-defined round center. The center of the infection is usually filled with white or yellow pus because of the pores. Pustules are usually hard and painful, and the skin around the bumps may be red and inflamed. 
  • Nodules – these are big, painful lumps of hard tissue that develop underneath the skin’s surface.
  • Cysts – the most acute kind of acne lesions are cysts, which are big pus-filled bumps that resemble boils and are most likely to result in permanent scarring.


Acne treatment is focused on eliminating comedones, combating increased oil production, reducing colonization by Propionibacterium acnes, and reducing inflammation. The kind of therapy generally relies on whether inflammatory lesions or comedones are more prevalent. No treatment works for everyone, so it is often necessary to try several to find the one that works best for each person.

Some products that do not require a prescription can be used when acne is mild, usually through local treatments. Utilizing more than one product is frequently more beneficial. For moderate acne, it is best to:

  • Keep your face clean by washing it with a neutral soap twice a day.
  • Avoid popping comedones or vigorously rubbing lesions.
  • Use medications that prevent the formation of comedones:
    • Topical retinoids. These are creams that have vitamin A in their composition, which reduces the formation of keratin and fat. Additionally, they are antibacterial and anti-inflammatory, which stops pores from clogging. Pregnant women should not use them.
    • Benzoyl peroxide. It eliminates bacteria and helps not to clog pores.
    • Salicylic acid.
  • Topical antibiotics (given as creams) such as azelaic acid, erythromycin, or clindamycin. They work by killing bacteria and reducing inflammation. They are usually used when there are inflammatory lesions.

When the acne is more severe, with significant inflammatory signs, or when it does not respond adequately to topical treatment after a few months, the use of systemic treatments (by mouth) should be considered:

  • Oral antibiotics. Its mechanism of action is the same as that of the topical ones, but they are stronger and have more adverse effects. In addition to antibiotic action, they have anti-inflammatory action. Oral antibiotics should be coupled with a topical retinoid to treat deeper cystic lesions.
  • Oral contraceptives. Some cases of acne are related to hormones. For this reason, contraceptives work in some selected women.
  • Isotretinoin (Vitamin A) oral. It is used in the treatment of stubborn or severe acne. It is very effective but can cause important side effects such as teratogenicity (ability to cause malformations in the fetus during pregnancy), hepatotoxicity (liver damage), hyperlipidemia (increased lipids in the blood), and pancytopenia (simultaneous decrease in red blood cells, white blood cells, and platelets in the blood). It requires careful patient selection, pretreatment counseling, and frequent blood tests. It shouldn’t be used before or during pregnancy since it might result in fetal problems. The typical dosage is daily for five months.
  • If acne improves, isotretinoin creams associated or not with benzoyl peroxide are usually used as maintenance treatment.
  • Acne scars can be treated with dermabrasion or laser facial resurfacing.


Contact a dermatologist or your healthcare practitioner if:

  • Over-the-counter medications and self-care techniques are ineffective after a few months. 
  • Acne is quite severe.
  • Your acne is deteriorating.
  • As your acne heals, scars develop.
  • Acne is causing mental and emotional stress.

Clare Louise

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