Pharmacological and Parenteral TherapiesQuestion 344 of 2368
A nurse withdraws medication from a vial. Why does the nurse first inject air into the vial?
- To warm the medication before it is drawn up
- To keep a pressure gradient so the solution can be withdrawn
- To make the medication sterile before it is drawn up
- To dilute the medication to a safer strength
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Correct answer: To keep a pressure gradient so the solution can be withdrawn
A vial is a closed system, so injecting air keeps pressure balanced and lets the solution come out.
Source: Nursing Skills, 2nd edition (Open RN, Chippewa Valley Technical College, 2023), Administration of Parenteral Medications: Vials. Licensed under CC BY 4.0.
Practice the topic "Pharmacological and Parenteral Therapies"Questions last reviewed: 18 October 2026