Objective:Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor is the cerstone of treatment in patients with acute coronary syndromes (ACS) and in those undergoing percutaneous coronary intervention (PCI).In current clinical situation,availability of different oral P2Y12 inhibitors (clopidogrel,prasugrel,and ticagrelor) has enabled physicians to switch among therapies owing to specific clinical scenarios.Although optimum time,loading dose and interval of transition between P2Y12 inhibitors is still controversial and needs further evidence,switching between oral inhibitors frequently occurs in clinical practice for several reasons.Data sources:This review was based on data in articles published in PubMed up to June 2018,with the following keywords antiplatelet therapy,ACS,PCI,ticagrelor and clopidogrel.Study selection:Original articles and critical reviews on de-escalation strategy in ACS patients after PCI were selected.References of the retrieved articles were also screened to search for potentially relevant papers.Results:Safety concs associated with switching between antiplatelet agents,has prompted the use of clopidogrel for patients with ACS especially after PCI as a de-escalation strategy.Practical considerations for de-escalating therapies in patients with ACS such as reducing dose of P2Y12 inhibitors or shortening duration of DAPT (followed by aspirin or P2Y12 receptor inhibitor monotherapy) as potential options are yet to be standardized and validated.Conclusions:Current review will provide an overview of the pharmacology of common P2Y12 inhibitors,definitions of deescalation and different de-escalating strategies and its outcomes,along with possible direction to be explored in de-escalation.