A report has been presented which emphasizes the need for caution in the use of ergotamine tartrate for the evaluation of autonomic nervous system influences on the electrocardiogram. A possible mode of action to explain the mechanism by which this acute coronary insufficiency pattern was precipitated, as a result of coronary vasoconstriction, is suggested. The relationship between the recurrent episodes of angina-like pain and the intravenous use of ergotamine is not determined at this time, although a similar episode of ten hours duration was noted in one of Scherf's² patients and substernal pain of nine hours duration following intramuscular injection has also been recorded.⁶