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Related to L-thyroxine: hypothyroidism, L-tyrosine


 (thī-rŏk′sēn′, -sĭn) also thy·rox·in (-rŏk′sĭn)
n. Abbr. T4
An iodine-containing hormone, C15H11I4NO4, produced by the thyroid gland, that increases the rate of cell metabolism and regulates growth. A synthetic form is used in the treatment of thyroid disorders.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(θaɪˈrɒksiːn; -sɪn) or


(Biochemistry) the principal hormone produced by the thyroid gland: it increases the metabolic rate of tissues and also controls growth, as in amphibian metamorphosis. It can be synthesized or extracted from the thyroid glands of animals and used to treat hypothyroidism. Chemical name: tetra-iodothyronine; formula: C15H11I4NO4
[C19: from thyro- + oxy-2 + -ine2]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(θaɪˈrɒk sin, -sɪn)

also thy•rox•in


a hormone of the thyroid gland that regulates the metabolic rate of the body: preparations of it used for treating hypothyroidism.
[1915–20; thyr- + ox- + in (dol) e (orig. thought to be a chemical component)]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


A hormone made in the thyroid that is important for growth and mental development.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.thyroxine - hormone produced by the thyroid glands to regulate metabolism by controlling the rate of oxidation in cells; "thyroxine is 65% iodine"
thyroid hormone - any of several closely related compounds that are produced by the thyroid gland and are active metabolically
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


, thyroxin
n. tiroxina, hormona producida por la tiroides que contiene yodo; se obtiene sintéticamente de la tiroides de animales y se usa en el tratamiento de hipotiroidismo.
English-Spanish Medical Dictionary © Farlex 2012


n tiroxina
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in periodicals archive ?
L-thyroxine (T4) is indicated for the treatment of myxoedema coma in adult patients.
Hypothyroidism is among the most frequent endocrine disorders, and levothyroxine (L-thyroxine) is one of the most commonly prescribed drugs by internists and endocrinologists in daily practice; however, inappropriate replacement of thyroid hormone is reported to be as high as 40% (1).
With L-thyroxine therapy, CK and TSH values were dramatically decreased and returned to normal at the second month of treatment as CK: 120 U/L and TSH: 2.68 [micro]IU/ mL, and a complete clinical improvement was observed.
She also had congenital hypothyroidism with normal thyroid ultasonography (TSH: >100 uIU/mL, sT4:0.7 ng/dL) and was euthyroid with L-thyroxine (12 mcg/kg/day).
Lipid profile in subclinical hypothyroidism: Is L-thyroxine substitution beneficial?
Serum levels of FT4 are correlated with erectile dysfunction and L-thyroxine treatment restores erectile function.7 Previous study has reported that thyroid hormones receptors are expressed both in penis corporal cavernosa endothelial and smooth muscle cells,20 and supplementation of L-thyroxine could improve function of endothelial and smooth muscle cells.7,21 SCH is much common in males with ED, and treatment of which may improve erectile function.
The Effect of L-Thyroxine on Metabolic Parameters in Newly Diagnosed Primary Hypothyroidism.
In this study, the effect of L-thyroxine treatment in patients with subclinical hypothyroidism was evaluated.
Determination of lodothyronine Absorption and Conversion of L-Thyroxine (T4) to (L-Triiodothyronine (T3) using Turnover Rate Techniques.
Overt hypothyroidism and subclinical hypothyroidism should be managed with l-thyroxine (category A drug), and TSH levels optimized to <2.5mIU/l, prior to conception.
Antonelli, "Oral L-thyroxine liquid versus tablet in patients with hypothyroidism without malabsorption: a prospective study," Endocrine, vol.
As was demonstrated by the work of Ladenson and Ridgway the treatment with 50 [micro]g L-triiodothyronine or 100 [micro]g L-thyroxine intravenous was able to result in reversal of blunted ventilator responsiveness, increase in cardiac inotropy, renal excretion of water load, and basal metabolic rate within hours to days after the start of treatment [25, 26].