Newborn heelstick blood collection can be a painful procedure in part because of the time required to obtain sufficient quantity of blood. No previous studies have determined whether local vasodilatation using topical nitroglycerine ointment (NGO) would facilitate heelstick blood collection. OBJECTIVE:To determine if the topical application of NGO would reduce the time needed to collect the required amount of blood for newborn metabolic screening and, in turn, reduce the pain/distress of the procedure. STUDY DESIGN:In a randomized, prospective, placebo controlled and blinded fashion, term newborns in a well nursery received either topical nitroglycerine or placebo ointment 10 minutes prior to heelstick. Total time and number of heelsticks required to complete the collection were measured along with crying time, heart rate and blood pressure. RESULTS:In all, 50 were studied, 25 in each group. There was no statistical difference between groups in collection time, crying time or number of heelsticks required for completion. Heart rate increased significantly and equally in both groups. Blood pressures were unchanged. CONCLUSIONS:Topical NGO did not facilitate heelstick blood collection or reduce the pain/distress of the procedure.