Abrupt withdrawal from clonidine therapy is a well-known cause of hyperadrenergic symptoms, but reports of acute myocardial infarction are extremely rare. We present the case of an 86-year-old woman who developed severe hypertension and a myocardial infarction 36 h after terminating her therapy of clonidine, 0.4 mg/day. Symptoms quickly responded to the administration of labetolol and diazepam. Subsequent cardiac catheterization showed no evidence of coronary occlusion, suggesting that excessive myocardial oxygen demand was responsible for the infarction.