Which medication is used to reverse the effects of heparin?

The medication used to reverse the effects of heparin is protamine. Heparin is an anticoagulant that inhibits blood coagulation and can lead to increased risk of bleeding. In situations where it is necessary to stop the effects of heparin, such as during surgery or in cases of heparin overdose, protamine serves as the antidote.

Protamine works by binding to heparin, forming a stable complex that neutralizes its anticoagulant properties. This reversal is particularly important in surgical settings where the restoration of normal clotting is critical for patient safety. The effectiveness of protamine in reversing heparin is well-established, making it the standard treatment in clinical practice for this purpose.

The other medications listed do not play a role in reversing heparin's effects. Thrombin is actually a pro-coagulant that helps in clot formation rather than reversing heparin. Lidocaine and Marcaine are local anesthetics and have no therapeutic use in neutralizing anticoagulants like heparin.