gOver 16 million people die every year by cardiovascular diseases, acute coronary syndrome is part of the spectrum.\cite{2000-20162018}A widely used approach is platelet aggregation inhibition by clopidogrel, drastically diminishing mortality but it doesn't works the same for everyone, a CYP2C19* 2 polymorphism could led your patient to a shorter life. How common is this? What about intermediate metabolizers? Do we need to think in alternative treatment? what is the importance of CYP2C19* 2 polymorphism versus other polymorphism? this and other topics would be addressed in this review.