Stability of Levothyroxine Sodium 0.4 μg/mL in 0.9% Sodium Chloride Injection

Abstract

Context Intravenous levothyroxine therapy decreases vasopressor requirements and prevents cardiovascular collapse in hemodynamically unstable patients eligible for organ donation. The stability of levothyroxine when used in this manner is unknown. Objective To determine the stability of levothyroxine solution for intravenous use at a concentration of 0.4 μg/mL diluted in 0.9% sodium chloride. Design Triplicate sample sets were prepared by reconstituting levothyroxine 200 μg for injection with 5 mL of 0.9% sodium chloride with further dilution in 500 mL of 0.9% sodium chloride. One sample set was protected from light and the other was left unprotected. Both sample sets were stored at room temperature, and samples from each were analyzed for initial concentration and 4, 8, 12, and 24 hours later. Conclusions Levothyroxine sodium 0.4 μg/mL in 500 mL 0.9% sodium chloride is stable for 24 hours at room temperature when protected from light.