Pruritus is a symptom with many causes but not a disease. Itchy patients fall into two groups: those whose pruritus is caused simply by surface causes (e.g. eczema, lichen planus and scabies, sunburn, psoriasis, insect bites) and those who may or may not have an internal cause for their itching (e.g. liver disease (biliary obstruction), chronic renal failure, iron deficiency, polycythaemia, thyroid disease (hyperthyroidism), diabetes, internal malignancy, neurological disease, diffuse scleroderma, pregnancy and drugs).These patients require a detailed physical examination, including a careful search for lymphadenopathy and investigations including a full blood count, iron status, urea and electrolytes, liver function tests, thyroid function tests and a chest X-ray.Unless a treatable cause is found, therapy is symptomatic and consists of sedative antihistamines, skin moisturizers, and the avoidance of rough clothing, overheating and vasodilatation, including that brought on by alcohol. Ultraviolet B often helps all kinds of itching, including the itching associated with chronic renal and liver disease. Local applications include calamine and mixtures containing small amounts of menthol or phenol.