What is Contact Dermatitis?
Also known as contact eczema, it is a type of eczema triggered by skin contact with a specific substance.
As with eczema, the skin becomes irritated, dry and inflamed after coming into contact with the substance in question which could be an irritant, or an allergen.
What are the symptoms of Contact Dermatitis?
The skin becomes dry, cracked, and flaky. It can become red, inflamed, and can be intensely itchy.
The symptoms can develop within hours of coming into contact with the irritant or allergen, or may take several days. In the case of an irritant, such as a chemical, you are more likely to notice the effect immediately, where as reaction to an allergen such as make up or jewellery can develop over a few days.
Although it can affect any part of your body, it most commonly affects your hands, arms, neck, face and legs.
What causes Contact Dermatitis?
There are two types of the condition;
- Irritant contact dermatitis
This happens when the skin comes into contact with an irritant such as chemicals, detergents and solvents that strip the skin of natural oils. It can also happen when you have frequent exposure to even a mild irritant such as soap or perfumes.
- Allergic contact dermatitis
This develops when the person has a sensitivity or allergy to a specific substance. The most common causes of this form of the condition are cosmetic ingredients, the metals in jewellery (usually cobalt or nickel), rubber including latex, the dyes in certain textiles, strong glues, some plants and topical medications.
Who is at risk of Contact Dermatitis?
Any person of any age, ethnicity or gender can be affected by the condition.
Patients with atopic eczema (the most common form) are at increased risk of being affected by irritants. Regular contact with water can also cause this form especially if the water is heavily chlorinated or treated.
Contact dermatitis is also more common in those who suffer from eczema, asthma or hay fever.
How does a dermatologist diagnose Contact Dermatitis?
A Dermatologist diagnoses contact dermatitis through examination and review of medical history. The Dermatologist may recommend patch testing which will help to determine which allergen has caused the reaction, what common products and substances contain the allergens and how to avoid the allergens in the future.
How does a dermatologist treat Contact Dermatitis?
Firstly through identified the allergens, a Dermatologist will advise on how to avoid contact with the allergens going forward.
Whilst it may not always be possible to avoid the substance completely (for examples with water), it is advised to create some sort of barrier between the substance and your skin e.g by wearing gloves.
In order to manage the rash a Dermatologist may prescribe topical cortisteroids and advise on how to repair the barrier function of the skin, through the regular use of emollients.
In severe cases of the condition a Dermatologist may prescribe oral steroids such as cyclosporine, methotrexate, azathioprine or alitretinoin or recommend phototherapy.
Where can I find more information on Contact Dermatitis? What patient support groups are available?
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