Psoriasis is a common skin condition that speeds up the life cycle of skin cells. It causes cells to build up rapidly on the surface of the skin. The extra skin cells form scales and red patches that are itchy and sometimes painful. Psoriasis is a chronic disease that often comes and goes. The main goal of treatment is to stop the skin cells from growing so quickly. There is no cure for psoriasis, but you can manage symptoms. Lifestyle measures, such as moisturizing, quitting smoking and managing stress, may help.