The objective of this chapter is to introduce the antiplatelet drugs. Antiplatelet drugs are a group of powerful medicines that prevent blood clots. When you are wounded, platelets arrive on the scene and group together to form a clot that stops the bleeding. This chapter covers the aspirin, clopidogrel, and prasugrel along with their indication, dose, contraindication, precaution, adverse effect, and drug interaction. Prophylaxis of myocardial infarction (MI) and stent implantation are the indications of aspirin. Hypersensitivity (attacks of asthma, angioedema, urticaria or rhinitis), active peptic ulceration; pregnancy (3rd trimester), children less than 12 years, patients with hemophilia or hemorrhagic disorders, gout, severe renal or hepatic impairment, and lactation are the contraindications of aspirin.