Heat rash, also called miliaria or prickly heat, is common in babies, but can affect adults as well. It is a type of rash that develops during the summer months, particularly when the weather is hot and humid. A heat rash is a type of skin irritation that develops when sweat gets trapped under the skin. This can lead to a variety of symptoms, such as itching, a prickly feeling, blisters or red lumps. Heat rash usually goes away on its own, once your skin cools down. If you are prone to heat rashes, the best way to prevent symptoms is to stay cool and out of the heat. If the symptoms are extremely severe, you can visit GoHealth Urgent Care for your rash, where a provider can help develop a plan for you.