Learn more about contact dermatitis, a common skin condition that can be caused by irritants or allergens. Find out about symptoms, treatments and preventive measures to better manage your contact dermatitis.
Contact dermatitis is an inflammation of the skin caused by direct contact with a particular substance. Find out more about the symptoms, causes and treatments to help you manage your contact dermatitis.
Caused by direct contact with irritants or allergens, contact dermatitis, also known as contact dermatitis, is an inflammation of the skin. Symptoms may include burning pain, skin rash, itching, dry skin or pruritus.
Irritant contact dermatitis, the most common form of dermatitis, is caused by direct contact with various substances that irritate the skin and cause inflammation.
Within 24 to 72 hours of skin contact, redness, edema, small pimples or red patches may appear.
In some cases, the reaction may take longer to appear, and may only manifest itself after several weeks or months of repeated contact with the substance responsible for the dermatitis.
Other symptoms may also appear, such as skin thickening, cracking, dryness and scaling.
The skin rash is limited to the area of contact with the substance.
Irritant contact dermatitis generally diminishes in intensity after 1 or 2 days post-reaction.
Allergic contact dermatitis is caused by direct contact with allergens. Specific immune cells are involved and sensitized to a substance. These cells become activated each time the skin comes into contact with the substance, causing a skin reaction.
Allergic contact dermatitis comprises two phases:
Sensitization to an antigen Allergic reaction after re-exposure
The sensitization phase, which is asymptomatic, can be brief (6 to 10 days) or prolonged (several years), depending on the sensitizers involved. Many allergens can cause contact dermatitis.
Symptoms range from erythema, desquamation and edema to vesiculation or severe swelling with bullae. Lesions often appear as linear striations on a leg or arm, or as circumferential erythema under a watch or belt.
Allergic contact dermatitis usually takes more than a day after exposure to become visible, and worsens over time.
A wide variety of chemicals are responsible for contact dermatitis. Particularly common in certain professions, contact dermatitis is largely under-detected, but it is estimated that 2-10% of the population1 is affected by this inflammation of the skin.
It is assumed that people suffering from contact dermatitis have an unfavorable allergic background.
Contact dermatitis is created by a substance that causes irritation on the skin, breaking down its protective barrier.
Irritant contact dermatitis is mainly caused by :
Soaps Detergents Chemicals Creams Diapers
Allergic contact dermatitis is a reaction of the immune system, which perceives the foreign substance as an enemy and triggers inflammation to fight it.
Allergic contact dermatitis is most often caused by :
Plants Metals (such as nickel or cobalt) Perfumes and by-products such as shampoos or soaps Latex Cosmetics Certain medications
Contact dermatitis is most often diagnosed on the basis of skin lesions and exposure history, but it may also require skin testing.
Clinical assessment
The appearance of the lesions, their location, and their evolution with the seasons or periods of activity, can guide the diagnosis towards the type of product responsible for the dermatitis. The patient's profession, hobbies, domestic occupations, recent travels, use of topical medications and cosmetics must all be taken into account in the clinical assessment.
Patch testing
When the cause of the reaction cannot be identified from the history, patch tests can be used. Patch tests are indicated when allergic contact dermatitis is suspected, but is not responsive to treatment, suggesting that the trigger has not been identified.
Patch tests are easy to use and can detect 36 of the most common allergens.
The test involves applying standard contact allergens to the upper back using adhesive strips. After 48 hours, the skin's reaction can be assessed, and the allergens responsible for allergic skin reactions identified.
This test may require up to 3 consecutive visits to an allergist or dermatologist.
However, patch testing only detects half of the clinically relevant contact allergens.
The key to relieving the symptoms of contact dermatitis is identifying and avoiding the substance responsible for the rash. As long as the person is exposed to the substance, the dermatitis does not go away. Redness and itching usually disappear from the skin 1 to 3 weeks after the last exposure.
Supportive care and topical or oral treatments are available to relieve the effects of contact dermatitis, such as itching.
Topical treatments consist of cortisone-based creams and are often prescribed to treat dermatitis and relieve itching.
Supportive care includes :
Cold water compresses to help reduce itching and burning. Moist dry dressings to absorb oozing bubbles and dry out the skin, thus promoting healing. Antihistamines for pruritus.
In the most severe cases of contact dermatitis, oral cortisone therapy may be required.
If the itching doesn't improve, and there is swelling of the skin with or without blistering, and signs of infection, you should consult your healthcare professional as soon as possible.
Atopic disorders increase the risk of irritant contact dermatitis, as the skin's barrier function is impaired.
Contact dermatitis can take up to 3 weeks to heal after stopping exposure to the substance responsible for the rash. Identified allergens should be avoided for life.
Identify triggering factors
If you experience the symptoms described for contact dermatitis, it's important to consult your healthcare professional. Only he or she will be able to diagnose and identify the agents responsible for your skin reactions.
Without a diagnosis, it's impossible to determine the factors triggering skin reactions, and to provide an effective solution and treatment.
Avoiding triggers
Difficult to live with, contact dermatitis is a skin condition that can have a major impact on your daily life. Intense itching can have a serious impact on sleep and quality of life. Visible patches and lesions can affect social relationships and the way others look at you.
Dans le cas d’une dermatite irritative de contact liée à votre profession provoquée par un ou plusieurs agents irritants cutanées, la question du changement de métier doit parfois être envisagée.
Il est recommandé de prendre toutes les précautions nécessaires pour éviter le contact avec les substances responsables des réactions cutanées et de consulter un professionnel de santé dès l’apparition des premiers symptômes.