Contact allergy

Allergy and Eczema

In the case of an allergy, the body reacts to a substance that is in itself harmless. The human immune system, which is responsible for the body's defences, misjudges the substance and regards it as a pathogen, resulting in a very severe reaction.

An allergy or hypersensitivity to a certain substance usually manifests itself in a negative reaction of the airways/mucous membranes (think of asthma and hay fever) or in a form of eczema. Eczema is a collective term for skin disorders in which the skin is red and often flakes and itches. Eczema can be dry (scaly) or wet (with vesicles that can burst open and release moisture). In a cosmetic allergy, a cosmetic ingredient causes a form of eczema. The cosmetic ingredient is the cause of a negative skin reaction and Eczema is the manifestation of that negative skin reaction. Allergy and eczema are therefore closely related, especially when it concerns an allergy to cosmetic products.

How does an allergy/ eczema develop

Eczema may be congenital (also called atopic eczema or constitutional eczema) or it may be a reaction to yeasts on/in the skin (e.g. dandruff) but it can also be caused by contact with an irritant aggressive substance (also called irritant eczema, ortho-ergic eczema, or non-allergic eczema, in which the skin reacts almost immediately to contact with an aggressive substance such as turpentine) or by contact with a substance that provokes an allergic reaction.

The latter is characteristic of eczema caused by cosmetics and is also called allergic contact eczema or contact allergy. Such an allergy does not arise immediately; it builds up over time. The skin has to come into regular contact with a substance for some time before the allergy actually develops. Sometimes this process can be completed within a few weeks, but it can also take years. For instance, one can tolerate a certain product for years until one suddenly becomes allergic to it. An allergic reaction can be intensified by damaged skin (e.g. with an open leg or if you already have congenital eczema), by cold, friction, sweat, light (e.g. an allergy to sun cream that only occurs when you are in sunlight), hay fever, or by another pre-existing form of eczema. Once one has a contact allergy (allergic contact eczema), it is often lifelong.

The substance that causes the allergic reaction is also known as an allergen. Not everyone reacts negatively to such an allergen. Only people whose immune system is sensitive to the allergen will be affected by it (the occurrence/non-occurrence of a negative reaction is determined by the way in which the immune system reacts to the substance in question).

Dermatological tests can be used to determine whether allergic contact eczema actually occurs and which allergen is the culprit. Research by the RIVM (commissioned by the Dutch Food and Consumer Product Safety Authority) has shown that the most common allergy in consumer products (not being foodstuffs) is the Nickel allergy. This allergy is generally caused by exposure to metal (clothing) accessories containing nickel. The next most common allergy is an allergy to certain cosmetics (this can be make-up, but also hair dye, shampoo, deodorant, etc). In general, this concerns an allergy to Perfume (mix), Perubalum or Cobalt Chloride (Perfume mix and Perubalum are used in almost all cosmetics (including make-up), the Cobalt Chloride is mainly used in hair dye).

How do you recognise allergic contact eczema?

The most characteristic feature is that the eczema is located where contact has been made with the allergen. In the case of a nickel allergy, you often see eczema around the navel (where the button of a jeans or the buckle of a belt touches the skin) or on the earlobe (where the earring sits) or under a watch band. In the case of a perfume allergy, you often see eczema behind the ears (where perfume is sprayed) or on the thin, vulnerable skin around the eyes (because you use eye cream containing perfume or because you rub your eyes with fingers painted with nail polish). The skin is then red and scaly and sometimes there are blisters and/or bumps on it. The blisters can be filled with fluid and even break open (with the risk of inflammation). In addition to these lesions, the skin often itches. Contact eczema is not contagious.

Do you suspect that you have an allergy?

When you experience an adverse skin reaction for the first time, it is tempting to jump to conclusions about the cause of the problem. However, it is advisable to thoroughly investigate what is causing the skin reaction. Often there are factors involved that are not initially thought of. For example, watery eyes after applying make-up can be caused by the make-up. But it can also be caused by an applicator (which contains latex, for example), by nail polish on the nails (where the fingers come into contact with the eyelids when applying eye shadow) or by the make-up cleaner used to clean the face beforehand.

If you suspect that you have suffered an allergic reaction to a cosmetic product, the following actions may be advisable:

• Performing a so-called 'elbow plexus test' yourself. If you suspect that you have an allergic reaction to a certain product, you can perform the elbow plexus test. This can only be done with products that remain on the skin for a long time, such as cream, body lotion or make-up (you cannot test in this way whether you are allergic to shampoo or bath foam, because these products are washed off the skin). You should then apply the product to the inside of the elbow twice a day for 14 days. If you have not had a negative skin reaction after 2 weeks, this generally means that you are not allergic to that product.

• Contact the family doctor. The general practitioner can give a referral to a dermatologist (skin specialist), for example. A dermatologist can determine whether an allergy to a particular ingredient exists by means of tests (with adhesive strips). And if that proves to be the case, the dermatologist can indicate which ingredient is causing the allergy (often several ingredients are involved). The dermatologist may indicate the trade name of an ingredient but also the 'inci name'. In order to be able to list cosmetic ingredients in a uniform way, it has been laid down by law that standardised names must be used for the ingredients, so-called INCI names (this stands for 'International Nomenclature Cosmetic Ingredients'). And once you know to which INCI names you are allergic, you can look at the list of ingredients (with INCI names) for each product. So if the ingredient you are allergic to is not on the list of ingredients of a product, you know that it is safe to use that particular product without having an allergic reaction. Useful to know: INCI names are listed with each product in order of decreasing weight. If a list of ingredients starts with, for example, aqua, the main ingredient of the product is water. Ingredients less than 1% present in the product may be listed in any order at the end of the ingredient listing.

What do you do if you know you have an allergy?

If you know what you are allergic to, it is wise to avoid the ingredient in question. That is why it is important to look closely at each product. The list of ingredients (INCI) is essential for this. For cosmetic products, manufacturers are obliged to state the INCI (on the product, or - if the product is too small - near the product or, for example, on the website associated with the product). Check this regularly, because over the years a manufacturer may change the composition of a product in the interim, as a result of which a product may suddenly give rise to an allergic reaction (because, for example, an updated formula has been used which adds an ingredient you are allergic to). Therefore, when buying a new product, always check the ingredient list, even if you have been using the product for some time without any problems. The fact that a product is hypo-allergenic, dermatologically tested, skin-friendly or naturally pure is never a guarantee!

Depending on the severity of the allergic reaction, a doctor may prescribe a cream, apply a special bandage (especially to prevent scratching of the skin) or possibly temporarily prescribe medication (prednisone) to calm the skin. In all cases, prevention is better than cure, and careful consideration of ingredients can prevent much suffering!

Allergies and Eczema have many manifestations and are extremely complex. In this article, we only provide general information based on studies and general publications. However, we are not medical experts.

If you suspect that you have an allergy, we therefore strongly recommend that you contact your doctor or a dermatologist for further personal advice.