Baby heat rash does not necessarily itch. Heat rash can be categorized into white heat, red heat, pus heat and deep heat. If your baby has white or dark heat rash, it is usually not itchy. If your baby has red prickly heat or pus rash, it will usually itch. 1. White prickly heat: The onset of the disease is in the stratum corneum or below the stratum corneum of the skin and is caused by sweat overflow from the sweat ducts. Often have drop-like blisters, transparent color, the size of a pinhead. Generally do not cause itching, pain and other conscious symptoms. 2. red prickly heat: the onset of the site is usually in the deeper sweat ducts, caused by sweat overflow sweat ducts. It is usually 2-4mm in size and is a dense papule with erythema at the base. Itchy and burning sensation is present at the lesions. 3. Pustular prickly heat: usually develops from red prickly heat. The shape is characterized by dense papules with pustules at the tip, the size of a pinhead. Itching and burning of the affected skin may occur. 4. Deep prickly heat: the onset of the disease is usually at the junction of the epidermis and the dermis, caused by repeated episodes of red prickly heat, resulting in rupture of the sweat ducts and blockage of sweat in the dermis. It is usually a hard pimple with the size of a sweat pore, which can be red or normal skin color. And the self-conscious symptoms are not obvious. If your baby has heat rash, you must go to a regular hospital to find out the cause of the disease and actively cooperate with professional doctors.