Triiodothyronine liothyronine

Liothyronine (triiodothyronine or T3) has approximately three times the potency of thyroxine (T4). 

Sodium Liothyronine. Sodium hothyronine [55-06-1] is the sodium salt of L-3,5,3 -triiodothyronine. It is made by the controlled iodination of L-3,5-diiodothyronine. It may be contaminated by starting material or L-T4. The USP assay (49) describes a chromatographic separation specifying 3,5-T2... 

Several studies have failed to confirm the benefits of combined levothyroxine and liothyronine therapy. Liothyronine given once a day results in non-physiological peak serum concentrations of T3. Modified-release triiodothyronine plus thyroxine can normalize serum biochemistry, but it is not known whether this formulation is superior to levothyroxine alone (12). 

Liothyronine (Cytomel) Increases triiodothyronine for short-term treatment... 

Hypothyroid is treated by administering levothyroxine sodium (increases thyroxine and triiodothyronine for long-term treatment), Liothyronine (increases triiodothyronine for short-term treatment), Liotrix (a mixture of levothyroxine sodium and liothyronine sodium), thyroid (seldom used), or thyroglobulin (seldom used). 

Liothyronine, 0-(4-Hydroxy-3 iodophenyl)-3,5-diiodo-L-tyrosine L-3-[4-(4-hydroxy-3-iodophertoxy)-3,5-diiodophenyljalanine 4 -(3 -iodo -4 -hydroxyphenoxy) -3,5 -diiodophenylalanine 3,5,3 -triiodothyronine T-3 Triothy-rone. C HyljNO mol wt 651.01. C 27 68%, H 1.86%, I 58.48%, N 2.15%, O 9.33%, Amino acid found in human plasma and thyroid gland, similar to thyroxine q-v. Gross, Pitt-Rivers, Lancet 1952, I, 439. Formation from diiodo-thyronine Roche et al., Biockem. Blophys. Acta 11, 215... 

Sodium salt, ClsHyIjNNaOj, liothyronine sedlum, sedfum L-triiodothyronine, Cytobin. Cytomine, Cytomel, Cynomel, Tertroxin, Triothyrone. The commonly used form. 

Thyroxine is bound to thyroid-binding globulin in the plasma, and is converted to triiodothyronine in the periphery. Thus, it has a slower onset and longer duration of action. Liothyronine, in contrast, is not bound and does not require conversion. Thus, it has a faster onset and shorter duration. 

Thyroid hormone is available as synthetic triiodothyronine (T3, or liothyronine), synthetic tetraiodothyronine (T4, levothyroxine), or natural desiccated animal thyroid (containing both T3 and T4 Table 11-55). Despite concern over the potentially life-threatening manifestations of thyrotoxicosis, serious toxicity rarely occurs after acute thyroid hormone ingestion. 

Synonyms 3,5,3 -Triiodothyronine liothyronine 0-(4-hydroxy-3-iodophenyl)-3,5-diiodo-L-tyrosine... 

Uses Thyroid hormones, levothyroxine (T4), and triiodothyronine (liothyronine, T3) are used to treat hypothyroidism. Both overt and subclinical hypothyroidism are associated with dyslipidemia, and replacement with thyroid hormones lowers the concentrations of serum low-density lipoprotein (LDL) cholesterol and has other potentially favorable actions on lipoprotein metabolism [1 ]. Consequently, thyro-mimetic drugs, which mimic the actions of thyroid hormones, hold promise as lipidlowering agents. The development of some of these drugs was discontinued because of adverse reactions related to thyroid hormone-like actions, including possible death due to cardiac causes and adverse effects on bone [2 , 3 ]. 

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