. . . . . . . . . . . . "Jivn-Ren Chen, Dimitri C. Papadimitriou, \"Stable dosage of levothyroxine sodium and process of production.\" U.S. Patent US5225204, issued November, 1991."@en . . . . "Levothyroxine acts like the endogenous thyroid hormone thyroxine (T₄, a tetra-iodinated tyrosine derivative). In the liver and kidney, T₄ is converted to T₃, the active metabolite. In order to increase solubility, the thyroid hormones attach to thyroid hormone binding proteins, thyroxin-binding globulin, and thyroxin-binding prealbumin (transthyretin). Transport and binding to thyroid hormone receptors in the cytoplasm and nucleus then takes place. Thus by acting as a replacement for natural thyroxine, symptoms of thyroxine deficiency are relieved."@en . " "@en . . "# Uchino H, Kanai Y, Kim DK, Wempe MF, Chairoungdua A, Morimoto E, Anders MW, Endou H: Transport of amino acid-related compounds mediated by L-type amino acid transporter 1 (LAT1): insights into the mechanisms of substrate recognition. Mol Pharmacol. 2002 Apr;61(4):729-37. \"Pubmed\":http://www.ncbi.nlm.nih.gov/pubmed/11901210 "@en . . . "3,5,3',5'-TETRAIODO-L-thyronine"@en . . "Oral administration with infant soybean formula, soybean flour, cotton seed meal, walnuts, foods containing large amounts of fiber, ferrous sulfate, and antacids may decrease drug absorption. "@en . . . . . . . "The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (monoiodotyrosine) and the coupling of iodotyrosines (diiodotyrosine) in the thyroglobulin. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form triiodothyronine which exerts a broad spectrum of stimulatory effects on cell metabolism. [PubChem]"@en . "> 99% to serum proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA), and albumin (TBA)"@en . . . . . . . . . . . . . . . . . "LT4"@en . . . . . . . . . . . . . "Bioavailability varies from 48% to 80%. Human studies have confirmed the importance of an intact jejunum and ileum for levothyroxine absorption and have shown some absorption from the duodenum."@en . . . . . . . . . . . . . . . . . . . . "LD₅₀=20 mg/kg (orally in rat). Hypermetabolic state indistinguishable from thyrotoxicosis of endogenous origin. Symptoms of thyrotoxicosis include weight loss, increased appetite, palpitations, nervousness, diarrhea, abdominal cramps, sweating, tachycardia, increased pulse and blood pressure, cardiac arrhythmias, tremors, insomnia, heat intolerance, fever, and menstrual irregularities."@en . . . . "O-(4-Hydroxy-3,5-diidophenyl)-3,5-diiodo-L-tyrosine"@en . . . "approved"@en . "L-T4"@en . . . . . . . "T4"@en . . . "For use alone or in combination with antithyroid agents to treat hypothyroidism, goiter, chronic lymphocytic thyroiditis, myxedema coma, and stupor."@en . . "51-48-9"@en . . . "Levothyroxin"@en . . . . . . . . . "Consistent administration in relation to meals is recommended."@en . . "Humans and other mammals"@en . . "Levothyroxine"@en . . . . . . . . . "4-(4-Hydroxy-3,5-diiodophenoxy)-3,5-diiodo-L-phenylalanine"@en . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "Absorption increased in fasting state and decreased in malabsorption states."@en . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "T₄, 6 to 7 days. T₃, 1 to 2 days."@en . "O-(4-Hydroxy-3,5-diiodophenyl)-3,5-diiodo-L-tyrosine"@en . . . . . . . . . . . . . . . . . . . . . . . "L-Thyroxine"@en . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "3,3',5,5'-Tetraiodo-L-thyronine"@en . . . "Thyroid hormones are primarily eliminated by the kidneys."@en . . . . . . . "Take 30-60 minutes before breakfast."@en . . "No iron or calium carbonate within 4 hours of taking this medication."@en . . . "Levothyroxine"@en . . . . . . . . . . . . .