Psoriasis is a chronic disease of the immune system that has symptoms ranging from scaly red patches appearing on this skin, to pitting and deformation of nails, to inflammation of joints. Any part of the body can be affected by psoriasis. As many as 7.5 million Americans have psoriasis, according to the National Institutes of Health. There are five types of psoriasis: plaque, guttate, inverse, pustular, and erythrodermic. Currently there is no cure for psoriasis, but there are treatment options available.

View Other Common Conditions