A red corn-like papule of the skin with intense itching and tingling sensation, commonly seen in hot and humid climates, caused by obstruction of sweat ducts or impaired drainage. Prickly heat is caused by obstruction of sweat ducts or impaired excretion. The formation of prickly heat is due to the high temperature and humidity in summer, the body sweats too much, not easy to evaporate, sweat impregnated epidermal keratin layer, resulting in the closure of the sweat gland ducts, sweat ducts in the storage of sweat, due to the increase in internal pressure and rupture, sweat infiltration into the surrounding tissue caused by stimulation, in the sweat hole at the occurrence of herpes and papules, prickly heat. It is also believed that the occlusion of sweat pores is a primary staphylococcal infection of the sweat pores, which is associated with a hot and humid environment. The diagnosis can be made by physical examination. 1. Red prickly heat: The most common clinical red prickly heat (red corn rash) is caused by sweat overflowing slightly deeper in the epidermis. It can occur at any age. It occurs on the back of the hands, elbow sockets, neck, chest, back, abdomen, under the breasts of women, and on the head, face, and buttocks of children, and is a dense, pinhead-sized, rounded papule or papule with a mild redness. The rash often appears in batches and is associated with a mild burning and tingling sensation. After the rash subsides, there is moderate to mild flaking. 2, white prickly heat: white prickly heat (crystal corn rash) is sweat in the stratum corneum or under the stratum corneum overflow. It is common in patients who sweat a lot in a hot environment, who are bedridden for a long time and who are overly weak. Most pinpoint to needle-sized, superficial small blisters with extremely thin walls, shiny, clear content and no redness occur on the neck and trunk. No conscious symptoms, easy to break after light rubbing, dry with very thin tiny scaly lips. Pustular prickly heat: Pustular prickly heat (pustular cornea) is a small superficial pustule with a pinhead at the tip. It is rare clinically and often occurs in folds, such as the flexors of the limbs and the pubic area, and is also common on the head and neck of children. The pustules are often sterile, or non-pathogenic cocci, but can become infected secondary to ulceration. Care: Do not scratch prickly heat with your hands and do not wash with strong alkaline soap. Do not use hot water to scald, but use warm water to rinse and dry, and sprinkle prickly heat powder. Patients with infection after scratching should apply antibiotic ointment.