During the procedure, small chambers containing allergens are affixed to the patient’s skin, usually on the upper back. These patches remain in place for 48 hours, during which the patient must avoid activities that could dislodge the patches, such as swimming or intense physical activity. After the exposure period, the patches are removed, and the skin is evaluated for any erythema, swelling, or vesicle formation. A follow-up evaluation is often conducted after 72 to 96 hours to confirm any late reactions.
