Economic Evaluation of a Pharmacist-Led 5-Day Therapeutic Hold of IV Levothyroxine at an Academic Medical Center

Abstract

Objective: Providers often admit patients with active outpatient prescriptions for levothyroxine. During an inpatient admission, providers may instruct critically ill patients to take nothing by mouth, or nil per os (NPO). Thus, they may prescribe the intravenous (IV) formulation of levothyroxine during this period. However, levothyroxine possesses a prolonged half-life of up to 7 days; therefore, immediate transition to IV levothyroxine may not be clinically necessary in the acute NPO setting. Intravenous levothyroxine is significantly more expensive than equivalent oral doses and may prove to be a financial burden for an institution. By understanding the pharmacokinetic properties of levothyroxine, we implemented a cost-saving initiative involving a 5-day therapeutic hold of IV levothyroxine. Methods: This was a retrospective evaluation in 2 intensive care units (ICU): a 20-bed surgical/trauma ICU and an 18-bed mixed medical/surgical ICU. Patient data, utilization data, and documented pharmacist interventions were collected for 6 months prior to implementation of the 5-day IV levothyroxine therapeutic hold and for 6 months post-implementation. All patients prescribed IV levothyroxine during these timeframes were included. Results: During the 6-month pre-implementation phase, 674 doses (691 vials) of IV levothyroxine for 77 unique patients were dispensed from the 2 ICUs. During the 6-month post-implementation phase, 168 doses (188 vials) of IV levothyroxine were dispensed for 44 unique patients. Of the 44 patients (48 orders) who still received IV levothyroxine, 22.9% of orders were deemed clinically necessary by the pharmacist and were not recommended to be held under the protocol, 64.6% were due to the verifying pharmacist being unaware of the protocol, 8.3% of orders were due to protocol non-compliance, and 4.2% were verified after the 5-day hold was complete as the patient remained NPO. This pharmacy-led initiative resulted in a 75% decrease in usage post-implementation and an estimated annualized savings of $80,000. Conclusion: A pharmacy-led initiative comprised of a 5-day therapeutic hold of IV levothyroxine was feasible and led to a 75% reduction in usage and cost over a 6-month period in 2 ICU’s. Future steps include additional staff education for improved protocol adherence and expanding the protocol institution-wide for an even greater cost-savings potential.