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Allergy and asthma
If you’ve ever used a new skin care or cleaning product and had your skin become itchy and red, you may have experienced contact dermatitis. 

Contact dermatitis is the rash that occurs when your skin has a reaction to something you come into contact with. This rash can be itchy and uncomfortable, and it can be caused by direct contact with a variety of substances. 

There are two types of contact dermatitis: 

  • Irritant contact dermatitis occurs when your skin is in contact with irritating substances, such as harsh cleaners and solvents.  
  • Allergic contact dermatitis occurs when your skin is in contact with something you are allergic to, such as fragrances or metals. The rash appears as a response from your immune system and may take weeks to heal. 
Contact dermatitis can co-exist and/or look similar to other skin conditions, such as eczema or atopic dermatitis. This makes it more difficult to diagnose, but there are signs and symptoms that can point to it being contact dermatitis.  

If you have a rash or bout of eczema that is new, chronic eczema that has changed, or a rash that isn’t responding to treatment, an allergist may evaluate for contact dermatitis. They will review your medical history, symptoms and exposure to different irritants and allergens. They may then suggest patch testing for diagnosis. 

What is patch testing? 

Patch testing can help uncover what substance or allergen your skin is reacting to. This is done by placing “patches” containing different substances that you may be allergic to on your back for two days. When the patches are removed, your allergist will examine your back for reactions. Based on your skin’s reaction, your allergist will create a treatment plan. 

Once diagnosed with contact dermatitis, treatment will largely involve avoiding the allergen or irritant that causes the reaction. Your allergist can help you create a plan to avoid the allergen, including sharing information on safe products that can be used. They may also suggest protective clothing and topical creams or gels that can help protect the skin. 

Contact a Prevea Allergist if you would like to learn more about contact dermatitis and patch testing.