Skin Conditions: What Is Actinodermatitis?

The sun's harmful effects are mainly caused by ultraviolet rays. UVB rays affect the epidermis, but UVA rays are more dangerous because they reach the dermis.
Skin Conditions: What Is Actinodermatitis?

Last update: 19 February, 2021

Actinodermatitis is a chronic skin condition attributed to the action of ultraviolet rays on the skin. We can easily prevent it by using sunscreen. That’s right, simply by using sunscreen we can instantly prevent this disease which often causes redness or spots on the skin.

This is true except in cases of people who are particularly sensitive to light; the treatment is preventive with the application of protective products that filter solar radiation. What are its causes? How can we recognize it?

Causes of actinodermatitis skin condition

The sun’s damaging effect is mainly caused by the ultraviolet rays received by the earth. UVB rays, although quantitatively smaller, are very powerful and affect the epidermis.

However, UVA rays are much more dangerous because they reach the dermis. These rays constitute the majority of the sun’s ultraviolet rays and are present all year round.

Actinodermatitis on skin.
Actinodermatitis is a dermatological disease attributed to the negative effects of the sun’s rays. It often causes redness, spots, and signs of premature aging.

Symptoms and manifestations of actinodermatitis

Immediate damage due to UVB rays, associated with prolonged and incorrect sun exposure, can be erythema, burns, and urticaria. However, their late effects are more complex. The main culprits are UVA rays, which penetrate deeply and generate:

  • Dark spots
  • Keratosis (thickening of the skin)
  • Premature aging
  • Degradation of membrane phospholipids

With the passage of time and after successive prolonged exposure to the sun, they can damage cellular DNA and develop a predisposition to the appearance of melanoma.

Effects of ultraviolet radiation on the skin

Ultraviolet radiation on the skin has consequences on the skin. Some of them are the following:

Aging of the skin and wrinkles

People who have spent many years of their lives working outdoors develop a more pronounced skin aging. This manifests itself by affecting the texture and elasticity of the skin and with a greater formation of wrinkles and spots.

Skin cancer

Sunlight is a risk factor in the development of skin cancer, both basal cell and squamous cell carcinoma and melanoma. About 90% of these cancers appear on areas of the skin exposed to the sun: the face, neck, ears, hands and forearms.

Allergic reactions

Some people develop allergic skin reactions. In certain cases, these reactions may appear after exposure to the sun. The symptoms may be red plaques, blisters or wheals, located in areas where the sun hits, such as the face, décolleté, arms, and hands.

How to prevent actinodermatitis

You have to protect your skin not only from UVB rays, but also from UVA rays. For this purpose, you can use broad-spectrum sunscreens to restore and maintain hydration and skin barrier functions.

Sun protection can help prevent sunlight-induced damage and reduce the risk of cancer. You should avoid the sun in the central hours of the day and wear appropriate clothing.

A woman applying sunscreen.
Using sunscreen is one of the most important measures to prevent actinodermatitis. People with delicate skin should choose a protection factor of at least 30.

Hat and parasol

You should wear suitable clothing that’s made out of sufficiently tightly woven fabric. In addition, wide-brimmed hats or caps can protect the facial region. You should also use sunglasses to protect your eyes.

Parasols and hats protect against UV rays that fall vertically, but not against diffuse light produced by reflections on water, sand and other surfaces. Remember to use these to avoid actinodermatitis and any other skin condition.

Use sunscreen

Sunscreen works by absorbing or reflecting the sun’s rays on the skin. The sun protection factor (SPF) is a number that should specify their UV blocking capacity.

Most are good blockers of UVB, which causes redness or sunburn. However, they don’t cover as much UVA which is more associated with skin damage and skin cancer.

Sunscreens should have a minimum protection factor of 15. People with lighter skin, with lighter eyes, who burn easily, need sunscreens with a higher index, such as 30 or 50.

No sunscreen has a duration of action of more than 2 hours, so it should be reapplied frequently. Especially in conditions of exercise, sweating, and swimming in water. In addition, we suggest applying them half an hour before sun exposure for them to be totally effective.

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