BACKGROUND The present study was done to analyze if glycoprotein IIb/IIIa inhibitors (GPI) bolus-only will reduce vascular/bleeding complications and cost with similar major adverse cardiac events (MACE) when compared with GPI bolus + infusion. Evidence-based therapy of GPI inhibitors during percutaneous coronary intervention (PCI) incorporates intravenous bolus followed by 12 to 18 hours of infusion. However, GPI bolus + infusion may increase vascular/bleeding complications and may not reduce MACE when compared with GPI bolus-only. METHODS From January 1, 2003, to December 31, 2004, 2,629 consecutive patients received GPI during PCI at a single center. Of these, 1,064 patients received GPI bolus + infusion in 2003 and were compared with 1,565 patients that received GPI bolus-only in 2004. Baseline characteristics were similar in both groups. RESULTS Patients receiving GPI bolus-only had reduced vascular/bleeding complications when compared with bolus + infusion (4.9% vs 7%, P < .05, odds ratio 0.62, 95% confidence interval 0.45-0.89). Furthermore, ischemic complications were similar in both groups, including periprocedural creatine kinase-MB enzyme release (12.8% vs 15.3%, P = NS), MACE at 30 days (3.2% vs 3%, P = NS), and death and myocardial infarction at 1 year (7.1% vs 7.8%, P = NS). In addition, GPI bolus-only reduced cost in US dollars ($323 vs $706, P < .001) and increased ambulatory PCI (13.1% vs 3.2%, P < .01), with reduced length of stay (1.1 vs 1.6 days, P < .01), when compared with GPI bolus + infusion. CONCLUSIONS Glycoprotein inhibitor bolus-only reduces vascular/bleeding complications with similar MACE and reduced cost when compared with GPI bolus + infusion. In addition, GPI bolus-only improved ambulatory PCI and reduced length of stay. These results are consistent with a safer and cost-effective strategy for bolus-only when GPI therapy is considered during PCI.