Antiplatelet Therapy Practice Test

Active bleeding is a contraindication to starting clopidogrel because this drug inhibits platelet aggregation and impairs clot formation. In the setting of ongoing intracranial hemorrhage or peptic ulcer bleeding, initiating therapy would worsen the bleed and hinder the body's ability to stop it, posing a serious, potentially life-threatening risk.

Other findings are not absolute barriers to starting therapy in all cases. Pregnancy often requires risk–benefit assessment rather than an outright contraindication, hypertension alone does not prevent use, and an allergy to clopidogrel would preclude therapy but the scenario’s decisive factor here is the presence of active bleeding, which makes initiating the drug unsafe.