Nitroglycerin has gained widespread acceptance as a drug for control of myocardial ischemia, as well as for induction fo hypotension during anesthesia and operation. A brisk increase in intracranial pressure (ICP) following the use of nitroglycerin for cardiac therapy in a patient with intracranial hypertension is described. This observation suggests a need for caution when using nitroglycerin in management of patients who have intracranial hypertension.