Side effects may occur from excessive doses.[1] This may include weight loss, fever, headache, anxiety, trouble sleeping, arrythmias, and heart failure.[1] Use in pregnancy and breastfeeding is generally safe.[2][1] Regular blood tests are recommended to verify the appropriateness of the dose being taken.[1]
Liothyronine was approved for medical use in 1956.[1] It is available as a generic medication.[2] In 2020, it was the 218th most commonly prescribed medication in the United States, with more than 2million prescriptions.[3][4]
Liothyronine may be used when there is an impaired conversion of T4 to T3 in peripheral tissues.[1] The dose of liothyronine for hypothyroidism is a lower amount than levothyroxine due it being a higher concentrated synthetic medication.[1] About 25 μg of liothyronine is equivalent to 100 μg of levothyroxine.[2]
In thyroid cancer or Graves' disease, ablation therapy with radioactive iodine (131I) can be used to remove trace thyroid tissue that may remain after thyroidectomy (surgical excision of the gland). For 131I therapy to be effective, the trace thyroid tissue must be avid to iodine, which is achieved by elevating the person's TSH levels.[5] For patients taking levothyroxine, TSH may be boosted by discontinuing levothyroxine for 3–6 weeks.[5] This long period of hormone withdrawal is required because of levothyroxine's relatively long biological half-life, and may result in symptoms of hypothyroidism in the patient. The shorter half-life of liothyronine permits a withdrawal period of two weeks, which may minimize hypothyroidism symptoms. One protocol is to discontinue levothyroxine, then prescribe liothyronine while the T4 levels are falling, and finally stop the liothyronine two weeks before the radioactive iodine treatment.[5]
Liothyronine may also be used for myxedema coma because of its quicker onset of action when compared to levothyroxine.[6] Use for the treatment of obesity is not recommended.[1]
DepressionEdit
Adding liothyronine to tricyclic antidepressants appears useful, especially in women.[7] An algorithm developed from the STAR*D trial recommends liothyronine as an option when people have failed two antidepressant medications.[8]
PregnancyEdit
Per the U.S. FDA, liothyronine is categorized as Pregnancy Category A.[9] Thyroid hormone is minimally transferred to the fetus or placenta, however as of October 2014, studies have not shown any adverse effects to the fetus. Hypothyroid mothers should continue to take thyroid hormone replacement therapy throughout pregnancy to avoid adverse events.[10][11]
NursingEdit
Breastmilk contains a low amount of thyroid hormone, so it is important to exercise caution when breastfeeding while taking liothyronine.[10]
ElderlyEdit
Older people should be started on lower doses of liothyronine.[9] Plasma T3 concentrations in this population are decreased by 25% to 40%.[10] TSH must be routinely monitored since there is a risk of coronary artery disease, hyperthyroidism and excessive bone loss from inadequate or abnormal thyroid replacement.[10]
ContraindicationsEdit
Any person with a hypersensitivity to liothyronine sodium or any active ingredient of the formulation should not be on this medication. If there is uncorrected adrenal insufficiency or thyrotoxicosis, a different approach to therapy must be considered.[9]
Side effectsEdit
Liothyronine may cause a number of side effects, mostly similar to symptoms of hyperthyroidism, which include:[12]
weight loss
tremor
headache
upset stomach
vomiting
diarrhea
stomach cramps
nervousness
irritability
insomnia
excessive sweating
increased appetite
fever
changes in menstrual cycle
sensitivity to heat
Boxed warningEdit
The package insert contains the following boxed warning, as do all thyroid hormones:[9]
Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.
PharmacologyEdit
Liothyronine is the most potent form of thyroid hormone. As a salt of triiodothyronine (T3), it is chemically similar and pharmacologically equivalent to T3. As such, it acts on the body to increase the basal metabolic rate, affect protein synthesis and increase the body's sensitivity to catecholamines (such as adrenaline) by permissiveness. As monotherapy or in combination therapy with SSRIs, liothyronine may also enhance generation of new neurons in the central nervous system.[13] The thyroid hormones are essential to proper development and differentiation of all cells of the human body. These hormones also regulate protein, fat, and carbohydrate metabolism, affecting how human cells use energetic compounds.
The British Competition and Markets Authority launched an investigation into the alleged "excessive and unfair pricing" of liothyronine tablets in 2017. It alleged that Advanz Pharma overcharged the NHS from before 2007 to July 2017. The price of a pack increased by almost 1,600% from £4.46 before it was debranded in 2007 to £258.19 by July 2017.[14]
ReferencesEdit
^ abcdefghijk"Liothyronine Sodium Monograph for Professionals". Drugs.com. Retrieved 27 February 2019.
^ abcBritish National Formulary: BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 757. ISBN9780857113382.
^"The Top 300 of 2020". ClinCalc. Retrieved 7 October 2022.
^"Liothyronine - Drug Usage Statistics". ClinCalc. Retrieved 7 October 2022.
^ abc"Thyroid Cancer (Papillary and Follicular)". American Thyroid Association. Retrieved 25 December 2016.
^Klubo-Gwiezdzinska J, Wartofsky L (March 2012). "Thyroid emergencies". The Medical Clinics of North America. 96 (2): 385–403. doi:10.1016/j.mcna.2012.01.015. PMID 22443982.
^Altshuler LL, Bauer M, Frye MA, Gitlin MJ, Mintz J, Szuba MP, et al. (October 2001). "Does thyroid supplementation accelerate tricyclic antidepressant response? A review and meta-analysis of the literature". The American Journal of Psychiatry. 158 (10): 1617–22. doi:10.1176/appi.ajp.158.10.1617. PMID 11578993.
^Gaynes BN, Rush AJ, Trivedi MH, Wisniewski SR, Spencer D, Fava M (January 2008). "The STAR*D study: treating depression in the real world". Cleveland Clinic Journal of Medicine. 75 (1): 57–66. doi:10.3949/ccjm.75.1.57. PMID 18236731.
^ abcdCytomel (Liothyronine Sodium) Drug Information: Warnings and Precautions - Prescribing Information at RxList, retrieved on 29-October-2014
^ abcd"Liothyronine (Lexi-Drugs)". LexiComp. Retrieved 29 October 2014.
^Montalvo JM, Wahner HW, Mayberry WE, Lum RK (August 1973). "Serum triiodothyronine, total thyroxine, and thyroxine to triiodothyronine ratios in paired maternal-cord sera and at one week and one month of age". Pediatric Research. 7 (8): 706–11. doi:10.1203/00006450-197308000-00006. PMID 4200034.
^MedlinePlus. "Liothyronine." Last accessed 14 July 2007.
^Rosenthal LJ, Goldner WS, O'Reardon JP (October 2011). "T3 augmentation in major depressive disorder: safety considerations". The American Journal of Psychiatry. 168 (10): 1035–40. doi:10.1176/appi.ajp.2011.10030402. PMID 21969047.
^. Pharmaceutical Journal. 31 January 2019. Archived from the original on 30 December 2019. Retrieved 17 March 2019.
External linksEdit
"Liothyronine". Drug Information Portal. U.S. National Library of Medicine.
liothyronine, this, article, about, liothyronine, medication, hormone, triiodothyronine, manufactured, form, thyroid, hormone, triiodothyronine, most, commonly, used, treat, hypothyroidism, myxedema, coma, taken, mouth, injection, into, vein, sodiumclinical, d. This article is about liothyronine as a medication For the hormone see Triiodothyronine Liothyronine is a manufactured form of the thyroid hormone triiodothyronine T3 1 It is most commonly used to treat hypothyroidism and myxedema coma 1 It can be taken by mouth or by injection into a vein 1 Liothyronine sodiumClinical dataTrade namesCytomel Tertroxin othersAHFS Drugs comMonographMedlinePlusa682462License dataUS DailyMed LiothyronineRoutes ofadministrationBy mouth intravenousATC codeH03AA02 WHO Legal statusLegal statusUK POM Prescription only Pharmacokinetic dataProtein binding99 7 Elimination half life2 5 daysIdentifiersIUPAC name sodium S 2 amino 3 4 4 hydroxy 3 iodophenoxy 3 5 diiodophenyl propanoateCAS Number6893 02 3 YPubChem CID16218759IUPHAR BPS2634DrugBankDB00279 YChemSpider17346129 YUNII06LU7C9H1VChEBICHEBI 6484 NChEMBLChEMBL1201119 NPDB ligandT3 PDBe RCSB PDB CompTox Dashboard EPA DTXSID8047505ECHA InfoCard100 000 203Chemical and physical dataFormulaC 15H 11I 3N Na O 4Molar mass672 959 g mol 13D model JSmol Interactive imageSMILES Na O C O C H N Cc2cc I c Oc1cc I c O cc1 c I c2 OInChI InChI 1S C15H12I3NO4 Na H2O c16 9 6 8 1 2 13 9 20 23 14 10 17 3 7 4 11 14 18 5 12 19 15 21 22 h1 4 6 12 20H 5 19H2 H 21 22 1H2 q 1 p 1 t12 m0 s1 YKey IRGJMZGKFAPCCR LTCKWSDVSA M Y N Y what is this verify Side effects may occur from excessive doses 1 This may include weight loss fever headache anxiety trouble sleeping arrythmias and heart failure 1 Use in pregnancy and breastfeeding is generally safe 2 1 Regular blood tests are recommended to verify the appropriateness of the dose being taken 1 Liothyronine was approved for medical use in 1956 1 It is available as a generic medication 2 In 2020 it was the 218th most commonly prescribed medication in the United States with more than 2 million prescriptions 3 4 Contents 1 Medical uses 1 1 Depression 1 2 Pregnancy 1 3 Nursing 1 4 Elderly 2 Contraindications 3 Side effects 3 1 Boxed warning 4 Pharmacology 5 Pricing 6 References 7 External linksMedical uses EditLiothyronine may be used when there is an impaired conversion of T4 to T3 in peripheral tissues 1 The dose of liothyronine for hypothyroidism is a lower amount than levothyroxine due it being a higher concentrated synthetic medication 1 About 25 mg of liothyronine is equivalent to 100 mg of levothyroxine 2 In thyroid cancer or Graves disease ablation therapy with radioactive iodine 131I can be used to remove trace thyroid tissue that may remain after thyroidectomy surgical excision of the gland For 131I therapy to be effective the trace thyroid tissue must be avid to iodine which is achieved by elevating the person s TSH levels 5 For patients taking levothyroxine TSH may be boosted by discontinuing levothyroxine for 3 6 weeks 5 This long period of hormone withdrawal is required because of levothyroxine s relatively long biological half life and may result in symptoms of hypothyroidism in the patient The shorter half life of liothyronine permits a withdrawal period of two weeks which may minimize hypothyroidism symptoms One protocol is to discontinue levothyroxine then prescribe liothyronine while the T4 levels are falling and finally stop the liothyronine two weeks before the radioactive iodine treatment 5 Liothyronine may also be used for myxedema coma because of its quicker onset of action when compared to levothyroxine 6 Use for the treatment of obesity is not recommended 1 Depression Edit Adding liothyronine to tricyclic antidepressants appears useful especially in women 7 An algorithm developed from the STAR D trial recommends liothyronine as an option when people have failed two antidepressant medications 8 Pregnancy Edit Per the U S FDA liothyronine is categorized as Pregnancy Category A 9 Thyroid hormone is minimally transferred to the fetus or placenta however as of October 2014 studies have not shown any adverse effects to the fetus Hypothyroid mothers should continue to take thyroid hormone replacement therapy throughout pregnancy to avoid adverse events 10 11 Nursing Edit Breastmilk contains a low amount of thyroid hormone so it is important to exercise caution when breastfeeding while taking liothyronine 10 Elderly Edit Older people should be started on lower doses of liothyronine 9 Plasma T3 concentrations in this population are decreased by 25 to 40 10 TSH must be routinely monitored since there is a risk of coronary artery disease hyperthyroidism and excessive bone loss from inadequate or abnormal thyroid replacement 10 Contraindications EditAny person with a hypersensitivity to liothyronine sodium or any active ingredient of the formulation should not be on this medication If there is uncorrected adrenal insufficiency or thyrotoxicosis a different approach to therapy must be considered 9 Side effects EditLiothyronine may cause a number of side effects mostly similar to symptoms of hyperthyroidism which include 12 weight loss tremor headache upset stomach vomiting diarrhea stomach cramps nervousness irritability insomnia excessive sweating increased appetite fever changes in menstrual cycle sensitivity to heatBoxed warning Edit The package insert contains the following boxed warning as do all thyroid hormones 9 Drugs with thyroid hormone activity alone or together with other therapeutic agents have been used for the treatment of obesity In euthyroid patients doses within the range of daily hormonal requirements are ineffective for weight reduction Larger doses may produce serious or even life threatening manifestations of toxicity particularly when given in association with sympathomimetic amines such as those used for their anorectic effects Pharmacology EditLiothyronine is the most potent form of thyroid hormone As a salt of triiodothyronine T3 it is chemically similar and pharmacologically equivalent to T3 As such it acts on the body to increase the basal metabolic rate affect protein synthesis and increase the body s sensitivity to catecholamines such as adrenaline by permissiveness As monotherapy or in combination therapy with SSRIs liothyronine may also enhance generation of new neurons in the central nervous system 13 The thyroid hormones are essential to proper development and differentiation of all cells of the human body These hormones also regulate protein fat and carbohydrate metabolism affecting how human cells use energetic compounds In comparison to levothyroxine T4 liothyronine has a faster onset of action as well as a shorter biological half life which may be due to less plasma protein binding to thyroxine binding globulin and transthyretin Pricing EditThe British Competition and Markets Authority launched an investigation into the alleged excessive and unfair pricing of liothyronine tablets in 2017 It alleged that Advanz Pharma overcharged the NHS from before 2007 to July 2017 The price of a pack increased by almost 1 600 from 4 46 before it was debranded in 2007 to 258 19 by July 2017 14 References Edit a b c d e f g h i j k Liothyronine Sodium Monograph for Professionals Drugs com Retrieved 27 February 2019 a b c British National Formulary BNF 76 76 ed Pharmaceutical Press 2018 p 757 ISBN 9780857113382 The Top 300 of 2020 ClinCalc Retrieved 7 October 2022 Liothyronine Drug Usage Statistics ClinCalc Retrieved 7 October 2022 a b c Thyroid Cancer Papillary and Follicular American Thyroid Association Retrieved 25 December 2016 Klubo Gwiezdzinska J Wartofsky L March 2012 Thyroid emergencies The Medical Clinics of North America 96 2 385 403 doi 10 1016 j mcna 2012 01 015 PMID 22443982 Altshuler LL Bauer M Frye MA Gitlin MJ Mintz J Szuba MP et al October 2001 Does thyroid supplementation accelerate tricyclic antidepressant response A review and meta analysis of the literature The American Journal of Psychiatry 158 10 1617 22 doi 10 1176 appi ajp 158 10 1617 PMID 11578993 Gaynes BN Rush AJ Trivedi MH Wisniewski SR Spencer D Fava M January 2008 The STAR D study treating depression in the real world Cleveland Clinic Journal of Medicine 75 1 57 66 doi 10 3949 ccjm 75 1 57 PMID 18236731 a b c d Cytomel Liothyronine Sodium Drug Information Warnings and Precautions Prescribing Information at RxList retrieved on 29 October 2014 a b c d Liothyronine Lexi Drugs LexiComp Retrieved 29 October 2014 Montalvo JM Wahner HW Mayberry WE Lum RK August 1973 Serum triiodothyronine total thyroxine and thyroxine to triiodothyronine ratios in paired maternal cord sera and at one week and one month of age Pediatric Research 7 8 706 11 doi 10 1203 00006450 197308000 00006 PMID 4200034 MedlinePlus Liothyronine Last accessed 14 July 2007 Rosenthal LJ Goldner WS O Reardon JP October 2011 T3 augmentation in major depressive disorder safety considerations The American Journal of Psychiatry 168 10 1035 40 doi 10 1176 appi ajp 2011 10030402 PMID 21969047 CMA investigates 1 600 price increase of liothyronine over eight year period Pharmaceutical Journal 31 January 2019 Archived from the original on 30 December 2019 Retrieved 17 March 2019 External links Edit Liothyronine Drug Information Portal U S National Library of Medicine Portal nbsp Medicine Retrieved from https en wikipedia org w index php title Liothyronine amp oldid 1136537272, wikipedia, wiki, book, books, library,
