A 36-year-old man presented with a prolonged history of chest pain, and was given two sublingual nitroglycerin tablets. Subsequently, the patient became hypotensive, bradycardiac, apneic, and lost consciousness. The bradycardia resolved spontaneously. No evidence for acute myocardial infarction or ischemic disease was found. Thirty-four cases reported to date are reviewed, demonstrating that this response appears to be an independent effect of nitroglycerin taken in any form, in patients with and without myocardial infarction and to be unpredictable, especially without evidence of inferior or right ventricular infarction. Careful monitoring is warranted when administering nitroglycerin.