Patch testing for skin allergies

Patch testing is used to identify allergens that may be causing outbreaks of contact dermatitis – a localized rash or irritation of the skin where the allergen touched.

During patch testing, your Dermatologist will apply adhesive patches, which contain small amounts of the suspected allergens to your back. Two to three days later, your doctor will remove the patches and examine the skin to determine if there was a reaction(s). When the allergen is identified, your doctor can help educate you on how to avoid contact with that substance, which is the only way to prevent outbreaks of contact dermatitis. During the period where the patches are on your back, water and exercise should be avoided for best results as the patches need to remain affixed. Further, for most reliable patch testing, antihistamines and steroids (both topical and systemic) should be avoided for fourteen days prior to application.