Whereas the epidemic form of ergotism has been rare in the 20th century, the sporadic form has a wide distribution as a consequence of therapy with ergot-derivative drugs. Favourable prognosis of the condition, with complete recovery from the ischemic peripheral circulatory disorders can be obtained by early diagnosis. Precise evaluation of the history, with recognition of treatment of migraine headache or postpartum hemorrhage with ergot alkaloids, can be determinative in diagnosis. The specific pattern of the angiographic findings, as we saw it in 6 cases within the last 4 years, decisively confirms the diagnosis. We could demonstrate thread-, thorn- and hour glass-like narrowing of the vessels, due to spasm. Total occlusion with the development of collaterals may occur, but we saw no thrombus formation. The stenotic arterial segments had smooth margins. The distribution of the involved arteries was more focal than generalized and more peripheral than central. In two cases spasm could be abolished immediately by a pharmaceutical (i.a. injection of tolazoline) or by anesthetic procedures (halothane). The phenomenologic data, together with the complete reversal of the circulatory ischemic disorders after therapy (particularly the absolute ban of ergots) in most cases, is so specific that other diseases of ischemic nature (emboli, arteriosclerosis, Buerger's disease, fibromuscular hyperplasia) can be excluded.