CLINICAL ERGOTISM WITH LINGUAL ISCHEMIA-INDUCED BY CLARITHROMYCIN-ERGOTAMINE INTERACTION

The macrolide class of antibiotics, including erythromycin and trolean domycin, is associated with clinically significant adverse drug intera ctions. This results from macrolide inhibition of cytochrome P-450 met abolism of numerous xenobiotics, resulting in elevated serum drug leve ls and clinical intoxication. Animal studies, however, suggest that cl arithromycin, the newest approved macrolide antibiotic, has less poten tial for adverse drug reactions. We describe a patient who, on her fif th day of clarithromycin therapy, developed clinical ergotism (ie, hyp ertension, lingual ischemia, and peripheral cyanosis) several hours af ter administration of her usual 2-mg dose of ergotamine tartrate. To o ur knowledge, this is the first report of clinical ergotism precipitat ed by clarithromycin-ergotamine interaction and suggests that, like ot her macrolide antibiotics, ergot preparations should be avoided in pat ients who are taking clarithromycin.