Nodular itchy rash is a chronic, inflammatory skin disorder in which nodules appear on the extensor side of the extremities with severe itching. Etiology The etiology is unclear. Patients tend to experience allergies, and many are triggered by mosquito bites. Some patients may also have associated gastrointestinal disorders and endocrine disorders. Most nodular itch rash is a simple skin problem, but sometimes it can be a manifestation of systemic diseases such as AIDS and lymphatic diseases, while some other skin diseases, such as lichen planus and blistering, also have similar skin manifestations. Statistics also reveal that nodular itchy rash has a relationship with the individual’s mood. Clinical symptoms Itchy nodular rash is usually seen in young adults between the ages of 20 and 60, and can occur in both men and women. The main manifestation is the appearance of soybean to pea-sized nodules on the extremities, especially on the extensor side of the limbs, which are hard and have irregularly pigmented edges. Many patients start with papules and herpes at the site of mosquito bites and then gradually form harder, hemispherical nodules. Nodules are generally maroon, dark brown or normal skin color, and usually do not fuse with each other to form a sheet. The nodules may itch intensely and the itching may last from a few minutes to an hour or two at a time. The itching is so severe that the skin is often scratched and bleeding. The itching is usually more pronounced at night and during times of stress. Diagnosis Diagnosis of this disease does not require special tests. An experienced doctor can usually confirm the diagnosis based on the location, shape, itchiness and other symptoms of the nodules. Principles of treatment Prevention and treatment of insect bites and other triggering factors can play a preventive role. When nodules and itching appear, taking antihistamines and sedatives can relieve the symptoms; corticosteroids can be used in severe cases. Topical antipruritic drugs, other than strong steroid drugs, are not very helpful. At present, by injecting steroids into the lesion, or taking steroid drugs, is the more common way. Some people also use cryotherapy to freeze one lesion off, but this method tends to leave pigmented marks and scars.