Pruritus is a severe problem, especially in the elderly population, and poses a special challenge for diagnosis and treatment. Most of the pathophysiologic backgrounds of pruritus are still unknown. However the advances in basic neurologic research hold big chances to explain the pathophysiology of at least some of the different forms of pruritus. The causes of pruritus are miscellaneous on the molecular and clinical level. Though the dryness of the skin plays pathogenetically a crucial role in several kinds of pruritus such as pruritus in elderly and in atopic dermatitis. In the elderly population several other factors aggravate the pruritus of dry skin. These additional pruritic effects include diabetes mellitus, liver, kidney and thyroid diseases, malignant diseases and different drugs. Therefore, the investigation of pruritus involves several different medical domains and the therapy of pruritus always targets the different causes of pruritus. It is a combination therapy that is adapted to the patient.