Contact Dermatitis

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 Allergy patch testing is a diagnostic procedure used to identify substances that cause allergic skin reactions, particularly in cases of contact dermatitis. During the test, small amounts of potential allergens are applied to patches, which are then placed on the patient’s back and left in place for 48 hours. After removal, the skin is examined at specific intervals to check for signs of a reaction, such as redness, swelling, or itching at the test sites. This method helps doctors determine which substances—such as metals, fragrances, preservatives, or chemicals—are triggering allergic responses, allowing for targeted avoidance strategies and more effective treatment.