A sunburn is a more or less serious burn of the skin following a more or less long exposure to the sun, more particularly to its UVB rays. It causes redness, itchy pain and sometimes even blisters.


A sunburn, also called solar erythema, is a burn of the skin induced by the sun's ultraviolet rays: mainly UVB. They occur following excessive sun exposure and/or when the skin is poorly protected. Some skins are more fragile than others. In particular that of young children and people with light phototypes (red hair or blond with pale skin).

To know ! Repeated sunburn, particularly in early childhood, can cause skin cancer. It is one of the most common cancers. Every year there are nearly 70,000 new cases. You are at risk for skin cancer if you:

  • Hard to tan;
  • Have freckles;
  • Have more than 40 moles, some of which are larger than 5 mm;
  • Have a family history of melanoma;
  • Have had repeated sunburn;
  • Have lived for a long time in a country with high sun exposure;
  • Have a lifestyle or occupation that exposes you to the sun.

In addition, the sun is also responsible for the premature aging of the skin: wrinkles, sagging skin, appearance of lighter or darker spots.

In reality, tanning is a protective reaction of the skin against solar aggression. Beyond a certain threshold, the skin no longer tans, but reddens: this is sunburn. It causes the destruction of thousands of epidermal cells.

When an individual is exposed to the sun, two types of UV rays (Ultraviolet) reach him: UVB responsible for sunburn and UVA whose effect is not immediately visible, but which penetrates the skin more deeply. depth.

To know ! There are also UVCs which are very harmful, but fortunately completely filtered by the ozone layer.

UVB rays are the cause of tanning and sunburn. Note that 10% of them reach the deep layers of the skin. This explains the "delayed tan", visible a few hours after exposure. UVA rays, on the other hand, penetrate deep into the skin and damage it. This type of sunlight promotes the appearance of skin cancer. They cause pigmentation within minutes of sun exposure due to a chemical reaction occurring in skin cells. This is a temporary tan.

To know ! Solar radiation is made up of 39% visible radiation, 56% infrared and 5% ultraviolet. Part of the UV is stopped by the atmosphere and the ozone layer.

A distinction must be made between sunburn and sun allergy. Indeed, an allergy to the sun is manifested by small pimples in itchy red patches. The lesions are mainly present on the neckline, shoulders and limbs. This type of condition tends to increase over the years and affects women more readily.

Finally, there are also so-called phototoxic or photoallergic reactions. Low exposure to the sun can be enough to cause sunburn-type reactions due to taking a drug or product (perfumes, creams, deodorants).

Symptoms of a sunburn

Most often, a sunburn is manifested by:

  • Redness (or erythema) of the skin;
  • A pain ;
  • Sometimes itching.

There are several types of sunburn, depending on the severity of the burn.

  • The first degree burn that causes reddening of the skin, without blisters. It manifests within 6 to 24 hours of exposure. When you press on the reddened area, the color disappears. Sometimes itching is associated. This type of sunburn heals in a few days (maximum 1 week) and disappears without scarring or depigmentation. When the burn is more important, desquamation (the skin peels) can be observed.

  • When there are blisters, we are in the presence of a burn no longer of the first degree, but of the superficial second degree. They can appear immediately or within hours of exposure. The blisters are filled with a clear liquid with a red rim. Healing requires between 10 and 15 days without sequelae. On the other hand, the pain can be very important.

  • When the burn is more intense, it is called a deep second degree burn. The blisters are pale in color and the pain mild due to the destruction of nerve endings. In this case, healing is slower (one month) and scarring may result.

A medical consultation is necessary in case of:

  • Symptoms of sunstroke, i.e. fever, headache, nausea or vomiting;
  • Sunburn with blisters covering an area greater than half of the palm of the person's hand;
  • Extensive sunburn on a small child or infant.