Pharmacology and the Nursing Process by Linda Lane Lilley: Practice Exam 2026 - Free Pharmacology Practice Questions and Study Guide

Vitamin K is the antidote for an overdose of oral anticoagulants. Although Protamine sulfate is the antidote for heparin overdose, it is not effective for oral anticoagulants. Option B, Heparin, is also a type of anticoagulant and is not an antidote. Dipyridamole is not an antidote for oral anticoagulant overdose, but rather a medication used for preventing blood clots. Therefore, the correct answer is Vitamin K, as it is specifically used as an antidote for an overdose of oral anticoagulants.