OBJECTIVES: To describe treatment patterns of Glycoprotein Inhibitors (GPI) and clopidogrel in patients presenting with acute coronary syndrome (ACS). METHODS: A prospective observational registry in 3 countries, recruited ACS patients undergoing percutaneous coronary intervention (PCI), January – August 2007, capturing practice patterns, resource use and quality of life. RESULTS: A total of 1525 ACS pts (Spain-538, UK-504, France-483), mean age 62 (SD 12), mean wt 80kg (SD 15), 22% female were recruited. Index diagnosis: unstable angina (UA) and non ST-elevation myocardial infarction (NSTEMI) 62%; ST-elevation myocardial infarction (STEMI) 38%. Ninety-five percent of patients were treated with clopidogrel, whereas 34% of patients received GPIs (abciximab-21%; eptifibatide-3%); tirofiban-11%) before, during or after PCI. The overall use of GPIs was balanced between the three countries (Spain- 35% , UK- 33%, France- 36%). Abciximab was the most frequently used GPI and was administered mainly in the catherisation laboratory (76%) at the time of PCI. The small molecule GPIs were more commonly administered before PCI (eptifibatide- 55%; tirofiban- 78%) and to a lesser extent in the catherisation laboratory (eptifibatide- 42%; tirofiban- 19%). Of the patients who received abciximab, 60% were STEMI, 26% NSTEMI, and 13% UA. Administration of abciximab before PCI was more frequent in STEMI patients (23%) than in UA (5%) and NSTEMI patients (9%). CONCLUSIONS: Of the 34% of ACS patients receiving a GPI, abciximab was the most frequently used and was predominantly administered in the catherisation laboratory, whereas the other GPIs were more often initiated before. This fits with the NSTE-ACS guidelines recommendation of the European Society of Cardiology (ESC). In the STEMI abciximab cohort, an increase in pre-treatment could be observed.