Intravenous levothyroxine stewardship program at a tertiary academic medical center

Based on the pharmacokinetic profile of levothyroxine, a 3-day hold guideline for adult patients ordered for intravenous (IV) levothyroxine was implemented at a tertiary academic medical center. The purpose of this study was to evaluate the impact of the implementation of an IV levothyroxine hold guideline.

This single-center, retrospective analysis identified patients ordered for IV levothyroxine during a 13-week period before and after implementation of the guideline. The primary outcome was guideline adherence, defined as full implementation of the 3-day hold. Secondary outcomes included the number of IV levothyroxine administrations avoided in the post-guideline group, extrapolated yearly cost avoidance (EYCA) after guideline implementation, reasons for guideline non-adherence, and number of safety reports involving IV levothyroxine.

A total of 166 and 134 patients met inclusion criteria for the pre- and post-guideline groups, respectively. Guideline adherence was observed in 94 (70.1%) patients, resulting in 276 vials saved in the 13-week post-guideline period, which translated to an EYCA of $139,877. Forty orders (29.9%) were non-adherent to the guideline, with the most common reason stated as nil per os (NPO). No difference in safety outcomes was seen between the pre- and post-guideline groups, as evidenced by 1 safety report in each group.

We observed a high rate of adherence to an IV levothyroxine hold guideline. This was associated with a substantial cost savings over the study period with no increase in reported safety events. To our knowledge, this is the first published report of an inpatient IV levothyroxine 3-day hold guideline.