Eucerin®: UV-Protection

Photoprotection for allergy-prone skin

Sun allergies-rashes caused by sunlight
When exposed to the sun results in skin changes taking the form of nodules, blisters or plaques, the lay man speaks of a sun allergy. Behind this self-diagnosis lies a multitude of possible light-dependent skin changes and/or diseases which are differentiated only with difficulty. The following UV-induced skin reactions are always accompanied by itching and/or nodules, blisters or plaques.

Polymorphous light eruption (PLE)
Polymorphous light eruption (PLE) is the most common light-induced skin disease. Up to 20% of the population, in particular younger women, are affected by it. There are several morphological variants of PLE. If PLE is suspected, a dermatologist should always be consulted, since the diagnosis of PLE requires much experience and other skin diseases must be excluded.

The pathogenesis of PLE is the subject of intensive research. It seems to involve a delayed type of immune reaction triggered by UV radiation: in 75% of the cases by UVA radiation, in 10% by UVB radiation alone, and in the remainder by sensitivity to all radiation regions.

Free radicals as triggers of PLE
Oxidative stress with formation of free radicals, triggered by UV radiation, can cause cell damage, resulting in inflammatory reactions and the various symptoms of PLE.

With a special method, the chemiluminescence technique (UPE = Ultraweak Photon Emission), the formation of free radicals can be detected since their destructive action, is associated with the release of photons release photons (light quanta). In this method, defined skin areas are irradiated with UVA and the intensity and decay of the emitted photons/second measured. The result of the chemiluminescence measurement is a parameter for the oxidative condition of the skin. If fewer photons are measured after the application of an effective product, this is an indication of an antioxidant effect of that product.

Placebo-controlled, double-blind studies have shown that the radical scavenger complex of alpha-glucosylrutin and vitamin E has a clinically significant prophylactic effect against PLE-symptoms.

Polymorphic Light Eruptions (PLE)

AGR = alpha-Glucosylrutin

Acne aestivalis
Acne aestivalis is not triggered by UV radiation alone, but appears in combination with certain ingredients found in cosmetics or sunscreen products, such as emulsifiers, and subsequent UVA exposure. Mostly affected are middle aged women, frequently with a medical history of pubescent acne. A differential diagnosis is problematic, since the clinical profile resembles the symptoms of PLE.

The recommended medicinal prophylaxis for persons showing symptoms of PLE or acne aestivalis is an emulsifier-free sunscreen containing the radical scavenger complex alpha-glucosylrutin and vitamin E to build up and maintain effective defensive depots, as demonstrated in clinical studies.

Photoreactions triggered by applied externally or internally substances
A photoallergy is a delayed inflammatory reaction similar to contact dermatitis induced by UV action after sensitisation with certain substances. These skin reactions present themselves as itch nodules in places exposed to light. Photoallergens can be certain medicines such as anti-hypertensives, diuretics, psychiatric drugs, tetracyclines and sulfonamides, but also topically applied substances such as fragrances.

Recommended are sunscreens products without fragrance and emulsifiers, for instance products with hydrodispersion gels as the base that have a high protection factor.

acne aestivalis

Test substances:
: A: 0,25% AGR + 1% TA (HG) B: 0,1% AGR + 1% TA (HG) C: 0,1% AGR + 1% TA (O/W-emulsion) D: placebo (HG)

AGR = alpha-glucosylrutin
TA = tocopheryl acetate
HG = hydrodispersion gel

Recommended for prophylaxis against allergies caused by intolerance to chemical UV filters are sunscreens with micropigments, which safely protect especially photosensitive skin from sunburn and light-induced skin reactions. UV radiation is mostly reflected from the skin surface.

Persisting photoreaction
Following a photoallergic reaction some patients develop, a persisting photoreaction, i.e. despite elimination of the substances that trigger a photoallergy in a certain person, inflammatory reactions always reappear after exposure to light. The range of wavelengths triggering the reaction continually widens, with even visible light causing inflammatory reactions.

Very fine, especially skin-compatible, mineral micropigments cover the skin like a protective film. The micropigments reflect both UVA and UVB radiation directly from the skin surface.

For these patients, a broadband sunscreen is most suitable for the prophylaxis of photoreactions.

SUMMARY:

For use on allergy-prone skin, prophylactic sunscreen products should contain the radical scavenger complex of alpha-glucosylrutin and vitamin E, or be sunscreen products with a high protection factor and micropigments. The products should be, without exception, free from fragrance and colorants.