Fibromuscular dysplasia, antiovulent drugs, and ergot preparations.

Review of 21 articles reporting cases of fibromuscular dysplasia (FD) of the carotid arteries confirmed that 80-85% of cases are females as previously reported; antiovulent drugs and estrogen medications have been causally related to FD. 3/6 patients reported from personal experience had received ergot preparations. Regular use of ergot results in incapacitating headaches with or without symptoms of peripheral ischemia. The term "carotid ergotism" has been coined to describe the drugs effects on those vessels. The vulnerability of carotid and renal arteries to FD can be attributed to: 1) less stable vascular supply of these vessels; 2)stress and stretch which render the arteries particularly vulnerable to episodic ischemia; and 3) the monoclonal hypothesis which suggests that proliferating cells of an early arteriosclerotic plaque stem from 1 mutated cell. Thus FD it is hypothesized may result from inappropriate multiplication of cells in certain muscular arteries and such proliferation is enhanced by antiovulents.