How does one get porphyria?

Inherited: Typically inherited problem in the breakdown of red blood cells, in particular heme. The abdominal pain and crises can be set off by medications, alcohol, or low calorie diets. Medications that cause include but are not limited to barbiturates, anticonvulsants, estrogens, oral contraceptives, or even supplements (chromium for example).

Genetic: Rare genetic disorder- autosomal dominant, though some other types are associated with alcohol use, smoking, hepatitis c, hiv, etc.