The beneficial effects of cosmetics on the skin are widely known and valued, less is said about their adverse sensitizing properties. Meanwhile, many cosmetics and personal hygiene products, or more precisely some of their ingredients are strong allergens capable of causing allergic contact dermatitis (or irritation), phototoxic or photoallergic changes.
Where to start the test - what kind of cosmetic makes us feel?
First of all, you should put away all cosmetics and hygiene products that we suspect to cause allergies! After giving up using all cosmetics and personal hygiene for a period of about two weeks - the usual skin symptoms caused by allergic eczema usually disappear.
Flake tests
If we achieve the desired effect of healthy skin - you should be tested for contact allergens - i.e. perform the so-called epidermal patch tests. Epidermal patch tests are used to detect contact type sensitization. They confirm (or do not confirm) the allergic basis of skin eczema changes and are also a test detecting allergenic cosmetics. For this purpose, suspicious cosmetics are used as testers testing the reaction of healthy skin.
How does testing work?
On the unchanged patient's back skin, a paper roll (1x1cm) impregnated with an allergen of appropriate concentration and a control test with a neutral substrate is applied and left for 48 hours. Then the discs are removed and assessed where the eczema changes occurred. Skin changes induced in this way are in the form of allergic eczema. The degree of intensity of these changes - in the control sample should initially reveal an allergenic cosmetic.
The reaction of the skin to suspicious cosmetics is tested twice
The first reading is intended to indicate suspicious cosmetic preparations, perfumes, shampoos, etc. The second reading made after two days is of decisive importance. During this time, the so-called reactions nieswoiste / np. eczema from irritation /, and allergic changes become more pronounced. Thanks to this second reading - you can determine the list of cosmetics and substances found in them, which are contact allergens. Of course, cosmetics containing sensitizing substances should be excluded from use. Very carefully, after a week of quarantine, we restore care with substitutes for removed cosmetics. We check thoroughly beforehand whether they contain the same or similar sensitizing substances!
Negative test result - it's not allergic!
However, if the two-week quarantine does not result in the disappearance of skin lesions, it can be assumed that the symptoms are caused by skin diseases: seborrheic dermatitis, various acne types, perioral dermatitis, etc. In this case, the physician should determine exactly the type of disease and take the treatment. It lasts for at least 2-3 weeks, until the disappearance of visible symptoms. It is only after complete cure of dermatoses that the causes of allergic contact eczema or skin hypersensitivity can be determined using patch tests, if the physician deems it necessary.
Ed. Edward Ozga - Michalski
Consultation by prof. dr hab. Andrzej Danysz
