Erythromycin-associated ergotamine intoxication: arteriographic and electrophysiologic analysis of a rare cause of severe ischemia of the lower extremities and associated ischemic neuropathy.

Vasospasm associated with ergotamine is a well-known phenomenon. In this case report we present a rare drug interaction between erythromycin and ergotamine at normal doses causing lower extremity ischemia in a 36-year-old woman. Nitroprusside proved to be the treatment of choice. The response was dramatic and took place in a matter of hours in this patient. Ischemic monomelic neuropathy is a recently described entity in which axonal necrosis is caused by a loss of distal extremity blood flow. The association between erythromycin and ergotamine may be a dangerous pharmacologic combination; drugs that have a hepatic cycle with ergotamine derivatives must be used with caution.