Nodular itchy rash belongs to the category of Chinese medicine “horse scabies”, cicada shells with brown sugar can not treat nodular itchy rash, it is recommended that patients in need of timely medical advice. Cicada molt is the shell of the cicada insect black grasshopper, which is shed when it plummets. It is sweet in flavor and cold in nature. Attributed to the lung and liver meridians. It has the effect of dispersing wind-heat, relieving pharynx, transmitting rashes, brightening eyes and reducing cataracts (improving eyesight and blurred vision), and antispasmodic. It is used for wind-heat colds, sore throat and hoarseness, impenetrable measles, itchy rashes, red eyes and cataracts, convulsions, tetanus. Sarcoptic mange is often caused by exogenous wind poison, insect bites, and stagnation of qi and blood, and clinically manifests itself in the form of small, hard papules or mounds the size of soybeans on the limbs, hands, feet, waist, and buttocks, accompanied by paroxysmal itching and nighttime nervousness. If the patient belongs to blood stasis syndrome, the symptoms are hard and firm skin lesions, nodular hyperplasia and roughness, and its color is purple and dull, etc., the patient can use Blood Palace and Blood Stasis Soup. If the patient is suffering from dampness and toxicity, the symptomatic lesions are impregnated, the nodules proliferate into warts, the color is grayish-brown, the itching is intense, etc., then the whole insect formula can be used with additional subtraction, and if there is heat evidence of redness of the lesions, then the dioscorea villosa soup can be used with additional subtraction. It is recommended that patients in need of timely medical treatment, under the guidance of the doctor.