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Patching up your allergies: What is a patch test?

Nov 09, 2023
Patch testing results, showing multiple positives
Dr. Wendt discusses contact allergy testing and treatment.

A patch test is a skin test that involves applying small amounts of different substances to the skin to check for a delayed allergic reaction. It's often done on the back or arm and involves placing a patch with a small amount of the substance on the skin for 48-72 hours. The skin is then checked for any signs of irritation, redness, swelling or itching over the next 3-10 days. The test can help identify which substances a person may be allergic to and is often used in cases of contact dermatitis.

Contact dermatitis is a type of skin inflammation caused by contact with a substance that irritates the skin or triggers an allergic reaction. The skin may become red, itchy, and swollen, and may even develop blisters or dry, scaly patches. Common irritants include soaps, detergents, solvents, and certain plants, while common allergens include nickel, latex, and fragrances. Treatment may include avoiding the offending substance, using topical or oral medications to reduce inflammation and itching, and in severe cases, phototherapy or systemic medications.

Contact dermatitis and eczema are both skin conditions that can cause red, itchy, and inflamed skin, but they have different causes and patterns of occurrence.

Contact dermatitis is a localized skin reaction that occurs when the skin comes into contact with an irritant or an allergen. It usually affects the area of skin that was in contact with the offending substance and can cause burning, itching, redness, and swelling.

Eczema, on the other hand, is a chronic inflammatory skin condition that can occur anywhere on the body and often runs in families. It may be triggered by a variety of factors, including allergens, stress, and hormonal changes. Eczema can cause dry, scaly, or leathery patches of skin that may be itchy and inflamed.

While both conditions can cause similar symptoms, contact dermatitis is typically a more acute, localized reaction, whereas eczema is a chronic, more generalized condition. An Allergist-Immunologist or Dermatologist can help diagnose and treat both conditions.

If you would like to be tested for your allergies or believe you might be a good candidate for allergy shots, Dr. Wendt and the staff at Relieve Allergy, Asthma & Hives would love to help.

Relieve Allergy Asthma & Hives is located near Kierland Commons, Scottsdale Quarter, DC Ranch and Grayhawk at 21803 N. Scottsdale Road Ste. 200, on the corners of Deer Valley and Scottsdale Roads, and has convenient evening and early morning hours to accommodate your schedule.

Dr. Wendt is also available for telemedicine appointments as appropriate. Insurance plans accepted. Call 480-500-1902 today to schedule an appointment now and begin your allergy testing and treatment with Dr. Wendt at Relieve Allergy, Asthma & Hives in Scottsdale, Arizona.

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