Irritant or allergic contact dermatitis?
There are innumerable materials and substances that can trigger contact dermatitis, and as such it is very common. It has two types: irritant or allergic.
Irritant contact dermatitis
Irritant contact dermatitis is caused by an agent (whether chemical or physical) that causes damage to the skin. Examples include:
- volatile substances
- concentrated or aggressive surfactants
- acidic and basic substances
- corrosive agents
- abrasive substances
- dust and powder
- synthetic fabrics
- the cold
The resulting rash only affects the part of the skin that has come into contact with the irritant substance. Once the stimulus is removed, the rash spontaneously recedes.
Allergic contact dermatitis
Allergic contact dermatitis is caused by an allergen: that is, a substance that can trigger a skin allergy in a predisposed subject.
Allergenic agents include:
- Preservatives: isothiazolinones, parabens, and formaldehyde releasers
- Red, yellow, and blue disperse dyes used in fabrics
- Fragrances in cosmetics, cleansers, toothpastes, detergents, and scented substances
- Peru Balsam (which can be found in many kinds of products)
- Heavy metals, i.e., Nickel, Cobalt, Chrome (specifically, Potassium dichromate)
- Other substances, e.g., paraphenylenediamine, ethylenediamine, lanolin, thiurams, mercaptobenzothiazole, benzocaine, neomycin sulphate, resins, colophony, and so on.
The skin doesn’t react immediately but displays symptoms after contact with an allergen at least 12 or so hours later. It can have a rash for several days that will affect not only the point of contact with the triggering substance, but also the area around it.
How and where do symptoms of contact dermatitis appear?
Contact dermatitis will appear as an inflammatory skin reaction with the following symptoms:
The parts of the body most affected are:
- Hands: they often, if only accidentally, come into contact with various kinds of substances that can cause irritation or an allergic reaction in the skin (particularly in occupations such as hairdressers, stylists, cleaning attendants, and so on).
- Face: in particular, the soft skin of the eyelids comes into contact with various cosmetic and makeup products that contain fragrances and traces of heavy metals.
- Genitals: they are exposed to contact dermatitis through cleansers, topical medications, or residue of detergents on underwear. Often contact dermatitis in the genitals is mistaken for infections.
Hives: triggering factors and allergic reactions
Hives - often confused for contact dermatitis - can be identified by the appearance of welts, or raised erythematous lesions accompanied by intense itchiness.
They can also be mistaken for angioedema, a swelling of subcutaneous tissue. In most cases, hives are idiopathic, meaning they have an unknown cause. In such cases, they can be caused by physical stimuli (such as heat, pressure, friction), viral infections and bacteria, or from a strong emotional reaction to stress.
Hives of allergic origin, on the other hand, can be triggered by medications, pollens, and insect bites.
The triggering causes of hives aren’t always immediately identified. For this reason, it’s essential to refer to a doctor.
How to treat a skin allergy
To reduce the discomfort caused by contact dermatitis, it’s essential, above all, to isolate the triggering cause. To do so, you’ll need to refer to a dermatologist who will identify through patch tests the substance/s that triggered your skin reaction.
The specialist will be the one to diagnose you and tell you which treatment to follow.
Specific lenitive cosmetic products based in ingredients that can soothe skin itchiness or discomfort can help in addition to pharmacological therapy (or by themselves in minor cases).
It’s important, furthermore, to cleanse your skin gently, with cleansers free of aggressive surfactants, fragrances, or other ingredients that can provoke an allergic reaction.
It’s also essential to be very careful, even once the skin reaction has passed, regarding the cosmetic products and cleansers you use in your routine. You should make sure that they’re all formulated to reduce the risk of skin allergies as much as possible.
The products in our Ceramol Beta line are advised for the treatment of reddening and irritations triggered by a range of causes.
They restructure lipids in dry or reddened skin, reducing sensations of itchiness.
The above information is not medical advice. It is given purely as an indication and is not intended as a substitute for professional advice.