Medical conditions that cause itching include atopic dermatitis, hepatitis, insect bites, dry skin and impetigo, according to MedlinePlus. Depending on the medical condition, itching is either localized to one area or occurs all over the body.
Atopic dermatitis is a chronic skin condition that causes intense itching, notes Merck Manuals. Although the cause of the condition is unknown, it commonly occurs in people with allergic disorders, such as asthma and hay fever. Patients with atopic dermatitis experience a rash that always itches, leading to uncontrollable scratching. Scratching the rash increases the risk of contracting bacterial and viral infections that may lead to serious illness.
Hepatitis is a viral infection that causes widespread itching as the disease progresses or in patients with acute hepatitis, explains Everyday Health. The condition leads to a buildup of bilirubin in the body, which causes itching. Other symptoms of hepatitis include jaundice, abdominal pain, fatigue, discolored stools and digestive problems.
Impetigo is a skin condition usually localized to the face, neck and hands and mostly affects children, according to Healthline. The condition is very contagious and causes various symptoms, depending on the type of impetigo a patient has. The most common type of impetigo in children is impetigo contagiosa, which first appears as red sores around the nose and mouth. These sores burst and leave a red and itchy rash that is not painful.