Porphyria is a rare genetic disorder that affects the skin and/or nervous system. Porphyria is caused by specific abnormalities in the heme production process. Heme is a chemical compound that contains iron and gives blood its red color. Heme is incorporated into hemoglobin, a protein that enables red blood cells to carry oxygen from the lungs to all parts of the body. Heme also assists the liver in breaking down chemicals to be removed from the body.

Heme is produced in the bone marrow and liver. As the heme production process progresses; several heme precursors are created. If one of the heme enzymes in is deficient, precursors may accumulate in liver or bone marrow tissues, appear in excess in the blood, and get excreted in the urine or stool. The specific precursors that accumulate depend on which enzyme is deficient.

Individuals with Cutaneous Porphyria (affects the skin) develop blisters, itching, and swelling of their skin when it is exposed to sunlight. Individuals with Acute Porphyria (affects the nervous system) may suffer from pain in the chest or abdomen, vomiting, and constipation or diarrhea. During an attack, symptoms include muscle numbness, tingling, paralysis, cramping, and personality or mental changes. Certain triggers can cause an attack, including some medicines, smoking, drinking alcohol, infections, sun exposure, and stress. Attacks develop over hours or days and can last for days or weeks.