A stable liquid formulation for parenteral administration that includes levothyroxine or a pharmaceutically acceptable salt thereof. The formulation includes a low concentration of an antioxidant, an amino acid as a pH adjuster and a stabilization agent in an aqueous solution that has a pH of about 9 to about 11.5. The parenteral liquid formulation is a stable formulation that is supplied as a ready-to-use or ready-to-administer product in a container or vial.
