The nurse is preparing to administer a schedule II injectable drug and is drawing up half of the contents of a single-use vial. Which nursing action is correct?

A. Schedule II drugs are controlled substances with a high potential for abuse. Proper disposal requires a witness, usually another nurse, to verify and cosign the waste to ensure accountability and prevent diversion. B. Keeping the remaining drug in the patient’s drawer is unsafe and violates controlled substance regulations. Single-use vials should not be stored for later use. C. While documentation of administered medication is necessary, simply recording the unused amount in the patient’s chart is insufficient. Controlled substances require proper disposal with a witness. D. Controlled substances cannot be discarded in a general locked collection box without proper witnessing and documentation. The correct procedure is to have another nurse verify and cosign the waste before disposal.