An allergic reaction occurs when your body perceives a harmless substance—such as certain foods, pollen, or pet dander—as a threat. This causes your immune system to overreact in an attempt to keep you safe from that substance. Allergy rashes can be uncomfortable and shouldn’t be ignored.

Kanwaljit Brar, MD, a pediatric allergy specialist at the Pediatric Allergy Program at Hassenfeld Children’s Hospital at NYU Langone with advanced training in dermatology, provides information on three common types of allergy rashes—eczema, contact dermatitis, and hives—including treatment options and advice on what to do it the rash doesn’t go away after treating it.

“If you can, try making an appointment with a skincare specialist, like a dermatologist, rather than visiting an urgent care for help with a rash caused by an allergen,” recommends Dr. Brar. That said, if you are experiencing any more serious symptoms, like shortness of breath, you should seek help as quickly as possible.

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