There are red spots on the chest, consider the following conditions: 1. Allergic purpura: mainly in the chest, or limbs at the appearance of petechiae, petechiae, pressure does not fade, there is no itching or pain sensation. In clinical treatment, you can mainly apply rutin tablets, or vitamin C capsules, or compound glycopyrrolate capsules orally, and you can apply topical glyburide lotion for treatment. The disease is caused by allergies, or bacterial, viral, fungal and other infections that cause an immune vasculitis change. 2. Erythema multiforme: mainly appears edematous red spots, slightly protruding from the body surface, and can have a certain itchy feeling. It may be mainly caused by infection or allergic factors, and can be treated with oral loratadine capsules, 1 capsule once a day, and topical fluticasone propionate ointment, 1 capsule once a day.