The day is wonderful the sun is laughing – who is not going to get out into the light now? Our ideal of beauty and the sense of body cult do the rest: Hungry for tans, crowds of people on such days deliberately expose themselves to UV radiation. And thus also undress parts of the body that are otherwise covered and neglected by the sun. You enjoy the pleasant warmth and look forward to the tanned result. But for many it looks very different. The very first rays of sunshine leave itchy rashes with ugly reddening, blisters and wheals on the still winter-white skin of people with a predisposition to sun allergy. UV-A rays are to blame.
Sun allergy: causes
A sun allergy (polymorphic light eruption) is not a real allergy like hay fever . In people with a sun allergy, substances that cause allergy-like skin symptoms are created solely by the action of the sun’s UV rays. These only occur on the body parts exposed to the sun, such as neck, décolleté, upper arms and shoulders.
Sunlight contains ultraviolet light in different wavelengths. Most sun allergy sufferers are blamed for the longer-wave UV-A radiation, the so-called tanning radiation. The effect of UV-A radiation is associated with the formation of aggressive oxygen particles, which are said to play a causal role in solar allergy. When the body’s own messenger substance histamine is released, the skin vessels expand, which in turn causes heat, redness and itching .
The best protection is to avoid the sun
For now, substances that prevent the release of histamine – so-called antihistamines – help against the strong itching. These can also be taken to prevent sun allergy. They inhibit the skin’s allergic inflammatory reaction. Prevention can also be prevented by slowly getting the skin used to the sun – that is, slowly increasing the amount of sun bathing. Likewise, by taking vitamin A precursors (beta carotenoids).
The most effective protection is of course to avoid sunlight. If you are still exposed to the sun, you should apply sunscreen with a high sun protection factor and protect yourself with light cotton clothing.
A second known clinical picture, in which the sun plays a major role, is the Mallorca acne, which was actually named after the most popular holiday island of the Germans. With good reason, because the disease was first observed in Mallorca: sunbathing holidaymakers suffered from acne-like skin changes and itching. Even today, sun-hungry globetrotters in southern climes are still plagued by Mallorca acne. The face, neck and décolleté as well as the upper arm and back are particularly affected.
In contrast to polymorphic light eruption, Mallorca acne is caused by an interaction between the UV light from the sun and the ingredients of the cosmetics. It is mostly fatty substances in sun creams and body lotions that are responsible for the rash in combination with the sun. Switching to fat-free and emulsifier-free sun cosmetics helps those affected to get rid of Mallorca acne.
The photoallergic reaction is a real allergy because the immune system is involved. A wide variety of substances – from fragrances in cosmetics to chemical light filters in sun protection to medicines – can cause an allergic skin reaction in combination with sunlight. Itching, blisters, redness, oozing skin and crust formation are among the many symptoms that often only appear many hours after sun exposure.
In the phototoxic reaction, the skin is directly irritated by substances that can be “toxic” under the influence of the sun’s rays. Skin contact with certain plants – such as hogweed or meadow grass – can cause reddening of the skin, burning itching or swelling in sensitive contemporaries. The symptoms are reminiscent of severe sunburn . However, it is also possible that substances in the body and sunlight are not compatible. The skin often reacts “toxic” to the combination of certain medications and UV rays.
Tip: If you need to take medications such as antibiotics or anti- diabetes , rheumatism or high blood pressure , you should inquire before going on holiday whether there may be photoallergic or phototoxic reactions. A look at the package insert or a consultation in the pharmacy provide information.