Temporary and reversible clopidogrel, ticagrelor and prasugrel high on-treatment platelet reactivity associated to the concomitant use of morphine and fentanyl in acute coronary syndrome

Background: Recent evidence demonstrates that morphine significantly reduces absorption and delays onset of action of P2Y12-receptor inhibitors in patients with acute coronary syndrome. Case summary: 55-year-old male with inferior ST-segment–elevation myocardial infarction was treated with opioids previous and during primary angioplasty, developing temporary and reversible clopidogrel, ticagrelor and prasugrel high on-treatment platelet reactivity assessed by platelet function test. We treated with glycoprotein IIb/IIIa inhibitor as a bridge to obtain antplatelet effect by P2Y12–receptor inhibitors. Discussion: The interaction between opioids and oral P2Y12-receptor inhibitors in patients with acute coronary syndrome should be highlighted. Although morphine administration may potentially lead to detrimental clinical consequences by diminish of antiplatelet effect, its routine avoidance cannot be recommended until large scale trials be available. We suggest that if the use of morphine and other opioids is inevitable, utilization of platelet function tests to guide the antiplatelet treatment is an option.