What is the antidote for heparin-associated hemorrhage?

• A. Vitamin K
• B. Protamine sulfate
• C. Fresh frozen plasma
• D. Desmopressin

Answer: (B)

Reversing the anticoagulant effect of heparin in bleeding is achieved with protamine sulfate, which binds heparin to form an inactive complex and rapidly neutralizes its activity. This makes protamine the specific antidote for unfractionated heparin–induced anticoagulation. Vitamin K reverses warfarin, not heparin. Fresh frozen plasma would replace clotting factors but doesn’t directly neutralize heparin, and desmopressin helps with certain platelet function disorders, not heparin reversal. Note that low molecular weight heparin is only partially reversed by protamine, whereas unfractionated heparin is effectively neutralized.