Drugs that inhibit platelet aggregation and anticoagulants are widely used in primary and secondary prevention of thromboembolism and treatment of venous thrombosis. The use of these drugs is associated with an increased risk of bleeding during an endoscopic procedure, and their discontinuation leads to an increased risk of a thromboembolic event. The paper presents how to assess risk and how to prepare a patient treated with antiplatelet or anticoagulant drugs for endoscopic procedures. In each case, one should consider indications and planned duration of treatment as well as urgency of the procedure. Diagnostic gastroscopy and colonoscopy do not usually require treatment modification, while the procedures with increased risk of bleeding require a change in therapy. In the case of antiplatelet drugs, it may be needed to stop it at a proper time before endoscopy. In the case of a dual antiplatelet therapy, when there are absolute indications for its use, one should consider postponing the procedure. Patients with increased risk of bleeding, treated with vitamin K antagonists, should have the treatment temporarily stopped and replaced with a bridging therapy with low molecular weight heparin; if the thromboembolic risk is assessed as low, a bridge therapy is not needed. The time to suspend the use of oral anticoagulants which are non-vitamin K antagonists depends on the risk of bleeding and renal function. Decisions concerning treatment may require consultation of a specialist ordering the anticoagulant or antiplatelet therapy as well as the opinion of an endoscopy centre in which the procedure is to be conducted. The doctor performing the examination should be informed about the treatment used by the patient and its modification.

anticoagulant therapy, gastroscopy, colonoscopy, antiplatelet therapy, oral anticoagulants