A client is receiving IV vancomycin and the nurse plans to draw blood for a peak and trough to determine the serum level of the medication. Which collection times provide the best determination of these levels?

A. Immediately after completion of the IV dose and 30 minutes before the next administration of the medication: This timing is correct for monitoring vancomycin levels. The peak level is typically measured immediately after the completion of the infusion (though peak levels are less commonly required for vancomycin), and the trough level is measured just before the next dose is due, 30 minutes before administration. This approach helps in evaluating the medication's efficacy and safety. B. One hour after completion of the IV dose and one hour before the next administration of the medication: This timing is not ideal. The peak level for vancomycin is usually measured immediately after the dose rather than one hour later. Trough levels are measured closer to the next dose, typically 30 minutes before the next dose. C. Two hours after completion of the IV dose and two hours before the next administration of the medication: Measuring levels two hours after the dose completion is too late for a peak level. The trough level should be measured closer to the next dose, generally 30 minutes before the next administration. D. Thirty minutes into the administration of the IV dose and 30 minutes before the next administration of the medication: Measuring the level 30 minutes into the infusion is not appropriate for peak levels, which are typically measured.