Deep prickly rash, also known as deep corn rash, occurs on the trunk and extremities, manifesting as dense small blisters with clear, transparent contents, which increase in size when sweating, but are not obvious when not sweating, and have clear plasma outflow when punctured, without itching and other conscious symptoms, and the rash does not occur on the face and palmoplants. When the rash is widespread, except for the face, axillae, palmoplantar, sweat glands are blocked in the upper dermis, no sweating, patients may develop heat exhaustion or tropical sweating exhaustion, with headache, fatigue, lack of appetite, sleepiness and other systemic symptoms. The principle of treatment for deep heat rash is anti-inflammatory and antipruritic, and the most effective method is to place the patient in a cool environment. If there is no secondary infection, topical powder or lotion can be used, or cool anti-itch lotion can be used, ointments, pastes and oil preparations should not be used, and hot water and soap should be avoided; if secondary infection occurs, topical antibiotic preparations can be added; in severe cases, oral antihistamines can be taken. The duration of deep prickly heat is relatively short, and the rash will subside after proper treatment and cooler temperatures. Daily ventilation and heat dissipation should be strengthened to avoid excessive humidity; avoid scratching to prevent secondary infection; wear loose clothing and change wet clothes in time to keep the skin clean and dry.