Porphyria (por-FEAR-e-uh) refers to a group of disorders that result from a buildup of natural chemicals that produce porphyrin in your body. Porphyrins are essential for the function of hemoglobin — a protein in your red blood cells that links to porphyrin, binds iron, and carries oxygen to your organs and tissues. High levels of porphyrins can cause significant problems. There are two general categories of porphyria: acute, which mainly affects the nervous system, and cutaneous, which mainly affects the skin.