Itchy rash under jeans button indicating contact allergy
Contact allergies are relatively widespread in the population, but those affected often do not initially become aware of the connection between skin irritation and contact with certain substances. On the one hand, the allergic reaction - unlike, for example, a pollen allergy - occurs with a time delay, and on the other hand, the allergens are often found in clothing (for example in jeans buttons or belt buckles) or other, at first glance, suspect materials. Purely natural substances or plant substances are also to be considered here as possible triggers of contact allergy.
A contact allergy basically runs in two phases: a sensitization phase and a phase of the acute allergic reaction. Sensitization to certain allergens occurs when they come into direct contact with the skin over a long period of time. The substances react with the proteins of the skin and sensitize the so-called T-lymphocytes. If there is renewed contact with the allergen, there is an excessive immune reaction, which appears as an itchy rash or as contact eczema with redness, swelling and the formation of pustules, blisters and nodules (papules).
Contact allergy under the jeans button A contact allergy, for example, increases on the stomach at the level of the jeans button, since many people are allergic to nickel, which is contained in most jeans buttons. Belt buckles can also cause similar symptoms due to the nickel they contain. Furthermore, contact allergies are increasingly due to ingredients in cosmetics, shower gel and perfume. The symptoms usually go away on their own as soon as contact with the allergens is discontinued. However, this presupposes that the triggering substances are identified first.
Contact allergy often difficult to identify Determining allergens is one of the main problems with contact allergies. While the skin irritation on the stomach can still be assigned relatively easily after wearing the new jeans, especially if the discomfort increases when the pants are worn repeatedly, this is much more difficult in other cases of contact allergy. Especially since the time interval between the allergic skin reaction and the contact with the allergens significantly complicates the assignment. The response time could be “between hours and days”, the news agency “dpa” quotes dermatologist Arno Köllner from the professional association of German dermatologists (BVDD). Contact allergy is therefore referred to as late-type allergy.
Allergens must be identified and avoided. If a contact allergy is suspected, a dermatologist should be consulted urgently, according to Köllner, who then tries to identify the triggering allergens using an epicutaneous test. The substances are applied to the skin, fixed with plasters and left there for one to two days. The doctor then checks whether changes in the skin appearance appear under the respective samples. "With an allergy, the test reaction is already a small contact eczema," explained Köllner. If the dermatologist detects an allergy, the patients receive a so-called allergy passport in which the allergens are entered. In the passport, patients can also see where the relevant substances occur most frequently. After identifying the allergens, those affected should avoid contact with the substances immediately, as otherwise a very painful chronic contact eczema could develop, reports the news agency "dpa", citing Thomas Fuchs from the University Medical Center Göttingen and the Medical Association of German Allergists (AeDA). With this chronic form, skin thickens permanently, becomes cracked and itches unbearably.
If a contact allergy is suspected promptly to the dermatologist Elsbeth Oestmann from the Allergy Center of the Charité in Berlin and the European Foundation for Allergy Research (ECARF), the “dpa” press release explains that those affected already go to the dermatologist with the first symptoms of an acute contact allergy to avoid complications and allow the skin to heal quickly. This would mostly prescribe creams containing cortisone, but these should generally only be used for a short time. Although there are "a large number of preparations today that no longer have the effects as was previously feared - for example that the skin becomes thinner", it is still important to follow the doctor's instructions exactly when using them explained Oestmann. By avoiding the allergens, however, the complaints resolve in most people even without cortisone. Treatment that completely prevents the occurrence of corresponding allergic reactions in the future is, however, not possible for contact allergies, while, for example, in the case of pollen allergy, so-called hyposensitization certainly serves to overcome the allergy. If contact with the triggering substances is avoided consistently, this can lead to the overreaction of the immune system disappearing over the years and eventually no longer appearing at all.
Natural cosmetics can also trigger contact allergies With regard to contact allergies caused by cosmetics, Thomas Fuchs from the University Medical Center Göttingen explained in the “dpa” message that these can also be triggered by natural cosmetics, since the latter also often contain contact allergens, for example in the form of natural essential oils . The expert cited propolis (bees resin), arnica, milking fat and mare's milk as examples of the natural allergens. There are also "contact allergies to tea tree oil or chamomile flower extract," added Oestmann. In general, patients with known contact allergies should take a close look at the list of ingredients on the packaging, whereby the so-called INCI list as a directory of the components of cosmetics also provides an understandable translation of the named ingredients on the packaging for end users. (fp)