Discontinue use if angina, severe bradycardia & hypotension, resp failure, asystole/cardiac arrest occur. Patients w/ left main coronary stenosis, uncorrected hypovolemia, stenotic valvular heart disease, left to right shunt, pericarditis or pericardial effusion, autonomic dysfunction or stenotic carotid artery disease w/ cerebrovascular insufficiency, recent MI, severe heart failure, minor conduction defects (1st degree AV & bundle branch block), atrial fibrillation or flutter, accessory bypass tract, prolonged QT intervals; history of seizures or susceptibility to seizures; bronchospasm. Patients on controlled Na diet. Recent & post heart transplant patients. Not to be administered w/ dipyridamole. Not recommended during pregnancy. Not to be used during lactation. Childn 0-18 yr.