A gonadotropin releasing hormone analogue prevents cyclical attacks of porphyria

• Acute Intermittent porphyria is a genetic disease in which endogenous hormones affect clinical expression. Premenstrual exacerbations can occur, sometimes often, in women with this disease. Gonadotropin releasing hormone analogues can prevent ovulation by reducing secretion of luteinizing hormone and follicle-stimulating hormone. In six patients with well-documented acute intermittent porphyria and frequent cyclical exacerbations, daily administration of an agonistic gonadotropin releasing hormone analogue, ([ImBzl]-D-His⁶,Pro⁹-NET)gonadotropin releasing hormone, intranasally or subcutaneously for as long as 26 months reduced or eliminated premenstrual attacks and caused only minor side effects. Adjustments in dosage or route of administration were sometimes needed. We conclude that endocrine manipulation by treatment with a gonadotropin releasing hormone agonist will prevent neurovisceral attacks of acute intermittent porphyria due to cyclical changes in endogenous hormones and is a safe alternative to exogenous steroids, which may induce attacks of this disease.