Porphyria is categorized as congenital erythropoietic porphyria, erythropoietic protoporphyria, acute intergenerational porphyria, etc. Different types have different etiologies. 1. Congenital erythropoietic porphyria: autosomal recessive, due to defects in uroporphyrin synthase in the heme synthesis pathway. 2. Erythropoietic protoporphyria: Most of the cases are due to autosomal dominant inheritance (incomplete epistasis), and a few are recessive. It is caused by a defect in subtilisin protoporphyrin synthase in the heme synthesis pathway. 3. Acute intergenerational porphyria: autosomal dominant, due to defects in porphyrin biliverdinogen deaminase. 4. Variant porphyrias: autosomal dominant, due to defects in protoporphyrinogen oxidase. It can occur after taking certain drugs, alcoholism, and exposure to certain compounds. 5. Delayed-onset cutaneous porphyria: caused by defects in uroporphyrinogen decarboxylase in the heme synthesis pathway. At the same time alcoholism, the use of ashwagandha, barbiturates, sulfonamides, chloroquine, methyldopa, methylglucosamine, has been enrostanol, chlorosulfonylurea, oral contraceptives and other drugs, arsenic, lead, iron and other compounds, herbicides can be liver poisoning as a causative factor.