Background: Numerous worldwide clinical trials have proven the indisputably negative influence of morphine on the pharmacokinetics and pharmacodynamics of P2Y12 receptor inhibitors in patients presenting with acute coronary syndromes. The aim of this trial was to evaluate whether oral coadministration of an anti-opioid agent, naloxone, can be considered a successful approach to overcome 'the morphine effect'.
Methods: Consecutive unstable angina patients receiving ticagrelor and morphine with or without orally administered naloxone underwent assessment of platelet reactivity using Multiplate analyzer as well as evaluation of the pharmacokinetic profile of ticagrelor and its active metabolite, AR-C124910XX, at 9 pre-defined time points within the first 6 hours following oral intake of the ticagrelor loading dose.