Fifty-six patients with cardiac disease participated in a study to determine the effect of site placement on patient reports of headache and flushing after topical nitroglycerin ointment placement. Nitroglycerin was placed on the upper arm, chest, and pelvis in random order. Approximately 30 minutes after application, patients were asked to evaluate their headache and flushing using a visual analogue scale. No significant difference in the severity of side effects was found when the three sites were compared by multivariate analysis of variance with repeated measures. The clinical practice of instructing patients to vary the site placement of nitroglycerin ointment to avoid side effects was not supported.