A nurse is caring for a client prescribed Levothyroxine. Which nursing action is most appropriate regarding administering on an empty stomach in the morning and monitoring for signs of hyperthyroidism?

• 1 Peak and trough monitoring is generally not required for gentamicin because its therapeutic window is wide and short courses rarely cause toxicity; levels are typically reserved for patients with renal dysfunction, prolonged therapy, or concomitant use of other nephrotoxic drugs.
• 2 Draw both peak and trough levels simultaneously at the midpoint between doses, approximately 4 hours after the last dose and 4 hours before the next, to represent the average drug concentration; this method simplifies monitoring and is acceptable for some drugs with predictable kinetics.
• 3 Draw the peak level 1 hour after starting the IV infusion and the trough 1 hour before the next scheduled dose; these collection times reflect the drug concentration at the end of the infusion and the lowest level before redosing; this timing is commonly used for drugs with a short half-life and a narrow therapeutic index. ✓ Correct answer
• 4 Trough about 30 minutes before the fourth dose, then administer the dose, and draw the peak about 30 minutes after the IV infusion ends; goal traditional peak 5 to 10 mg/L for systemic gram-negative infections and trough less than 2 mg/L; once-daily extended-interval dosing uses a different sampling and nomogram-based protocol.

For study reference only. Always follow current clinical guidelines and your institution’s protocols.