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The thionamide anti-thyroid drugs namely carbimazole, methimazole, and propylthiouracil, have been the predominant therapy modality for Graves' hyperthyroidism for over 60 years. Although these agents have proven efficacy and favorable side-effect profiles, non-thionamide alternatives are occasionally indicated in patients who are intolerant or unresponsive to thionamides alone. This review examines the available non-thionamide drug options for the control of Graves' hyperthyroidism and summarizes their clinical utility, efficacy, and limitations. We reviewed existing literature on mechanisms, therapeutic utility, and side-effect profiles of non-thionamide anti-thyroid drugs. Established non-thionamide agents act on various phases of the synthesis, release, and metabolism of thyroid hormones and comprise historical agents such as iodine compounds and potassium perchlorate as well as drug repurposing candidates like lithium, glucocorticoids, beta-blockers, and cholestyramine. Novel experimental agents in development target key players in Graves' disease pathogenesis including B-cell depletors (Rituximab), CD40 blockers (Iscalimab), TSH-receptor antagonists, blocking antibodies, and immune-modifying peptides. Non-thionamide anti-thyroid drugs are useful alternatives in Graves' hyperthyroidism and more clinical trials are needed to establish their safety and long-term efficacy in hyperthyroidism control. Ultimately, the promise for a cure will lie in novel approaches that target the well-established immunopathogenesis of Graves' disease. [ABSTRACT FROM AUTHOR]

Introduction: Recent prescribing policies in England and Wales have imposed significant restrictions on liothyronine prescribing in general practice driven by the prohibitive costs and uncertain benefits of liothyronine in the management of hypothyroidism. However, the impact of these policies on liothyronine usage and costs is still unclear. Methods: Data were downloaded from the NHS monthly General Practice Prescribing Data in England and from the Comparative Analysis System for Prescribing Audit (CASPA) in Wales for 2011–2020. Trends over the period in amount and costs of levothyroxine and liothyronine prescribing were analysed. Results: The total medication costs per year for England Wales for hypothyroidism rose from £60.8 million to £129.8 million in 2015–16 and have since reduced to £88.4 million. Levothyroxine prescriptions have been growing above the population growth rate at 0.7%/annum in England and 1.1% in Wales. The costs/patient/year for liothyronine rose from £550 to £3000 in 2015–16 and has since fallen to £2500. Use of liothyronine as a percentage of levothyroxine started to fall in 2015–16 at 7%/annum in England and 3% in Wales. Nevertheless, 0.5% of levothyroxine‐treated patients continue to receive liothyronine. All Clinical Commission Groups (CCGs) in England continue to have at least one liothyronine prescribing practice and 48.5% of English general practices prescribed liothyronine in 2019–20. Conclusion: In spite of strenuous attempts to limit prescribing of liothyronine in general practice, a significant number of patients continue to receive this therapy. The price differential of liothyronine vs levothyroxine should be examined again in light of the continuing use of liothyronine. [ABSTRACT FROM AUTHOR]

Summary: Uncorrected thyroid dysfunction in pregnancy has well‐recognized deleterious effects on foetal and maternal health. The early gestation period is one of the critical foetal vulnerability during which maternal thyroid dysfunction may have lasting repercussions. Accordingly, a pragmatic preconception strategy is key for ensuring optimal thyroid disease outcomes in pregnancy. Preconception planning in women with hypothyroidism should pre‐empt and mirror the adaptive changes in the thyroid gland by careful levothyroxine dose adjustments to ensure adequate foetal thyroid hormone delivery in pregnancy. In hyperthyroidism, the goal of preconception therapy is to control hyperthyroidism while curtailing the unwanted side effects of foetal and maternal exposure to antithyroid drugs. Thus, pregnancy should be deferred until a stable euthyroid state is achieved, and definitive therapy with radioiodine or surgery should be considered in women with Graves’ disease planning future pregnancy. Women with active disease who are imminently trying to conceive should be switched to propylthiouracil either preconception or at conception in order to minimize the risk of birth defects from carbimazole or methimazole exposure. Optimal strategies for women with borderline states of thyroid dysfunction namely subclinical hypothyroidism, isolated hypothyroxinaemia and thyroid autoimmunity remain uncertain due to the dearth of controlled interventional trials. Future trial designs should aspire to recruit and initiate therapy before conception or as early as possible in pregnancy. [ABSTRACT FROM AUTHOR]

Background: Suboptimal thyroid hormone therapy including under-replacement and over-replacement is common amongst patients with hypothyroidism. This is a significant health concern as affected patients are at risk of adverse cardiovascular or metabolic consequences. Despite a growing body of evidence on the effects of various factors on thyroid hormone replacement, a systematic appraisal of the evidence is lacking. This review aims to appraise and quantify the extent to which clinical, behavioural and pharmacogenomic factors affect levothyroxine therapy in patients with primary hypothyroidism. Methods/design: The databases Web of Science, Cochrane Library, EMBASE and PubMed will be searched. Patients must be adults over the age of 18 years, suffering from primary hypothyroidism including overt and subclinical hypothyroidism and receiving levothyroxine treatment. Studies in children, pregnant women and patients with secondary or tertiary hypothyroidism will not be included. We will also exclude studies focused on forms of thyroid hormone replacement therapy other than levothyroxine. The primary outcome is to quantify the effect of clinical, behavioural and pharmacogenomic factors on thyroid stimulating hormone (TSH) levels. Secondary outcomes are the effect these factors have on thyroxine (T4) and triiodothyronine (T3) levels, mortality, morbidity, quality of life, treatment complications, adverse effects, physical and social functioning. Studies will be screened through reading the title, abstract and then full text. Two reviewers will independently extract the data and select articles, and a third reviewer will be consulted if there is any disagreement. We will undertake a meta-analysis of studies in which there is a defined intervention or exposure, patients are receiving levothyroxine for hypothyroidism, there is an appropriate control group of levothyroxine treated patients that are not exposed to the intervention, and the primary outcome is determined by serum TSH levels. Studies will comprise of randomised controlled trials as well as observational data. Eligible studies will be assessed for bias using the risk of bias tool available in the Cochrane handbook 2011, and the quality of evidence will be judged according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. A flow diagram describing the data search will be created according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis: The PRISMA statement. A narrative synthesis will be undertaken in the description of the data, and summary tables will be created of the results. Discussion: This review will be the first systematic review of this nature. The evidence synthesised will be useful to general practitioners in their management of hypothyroidism. Findings will be disseminated at conferences and in professional and peer-reviewed journals. [ABSTRACT FROM AUTHOR]

The management of primary hypothyroidism with levothyroxine (L-T4) is simple, effective and safe, and most patients report improved well-being on initiation of treatment. However, a proportion of individuals continue to suffer with symptoms despite achieving adequate biochemical correction. The management of such individuals has been the subject of controversy and of considerable public interest. The American Thyroid Association ( ATA) and the European Thyroid Association ( ETA) have recently published guidelines on the diagnosis and management of hypothyroidism. These guidelines have been based on extensive reviews of the medical literature and include sections on the role of combination therapy with L-T4 and liothyronine (L-T3) in individuals who are persistently dissatisfied with L-T4 therapy. This position statement by the British Thyroid Association ( BTA) summarises the key points in these guidelines and makes recommendations on the management of primary hypothyroidism based on the current literature, review of the published positions of the ETA and ATA, and in line with best principles of good medical practice. The statement is endorsed by the Association of Clinical Biochemistry, ( ACB), British Thyroid Foundation, ( BTF), Royal College of Physicians ( RCP) and Society for Endocrinology ( SFE). [ABSTRACT FROM AUTHOR]

The subject of universal thyroid screening in pregnancy generates impassioned debate. Thyroid dysfunction is common, has significant adverse implications for fetal and maternal well-being, is readily detectable and can be effectively and inexpensively treated. Furthermore, the currently recommended case-finding strategy does not identify a substantially proportion of women with thyroid dysfunction thus favoring universal screening. On the other hand subclinical thyroid dysfunction forms the bulk of gestational thyroid disorders and the paucity of high-level evidence to support correction of these asymptomatic biochemical abnormalities weighs against universal screening. This review critically appraises the literature, examines the pros and cons of universal thyroid screening in pregnancy, highlighting the now strong case for implementing universal screening and explores strategies for its implementation. [ABSTRACT FROM AUTHOR]

The article focuses on hypothyroidism, a condition in which the body lacks sufficient thyroid hormone, which carries significant morbidity and is associated with increased risk of lipid disorders, cardiovascular disease and osteoporosis. It highlights several treatment recommendations including levothyroxine therapy, levothyoxine and liothyronine (L-T3) combination therapy, and compounded thyroid hormones.

An 82-year-old female with known hypothyroidism was admitted to hospital after being found on the floor. On examination, she was unkempt, confused, bradycardic, hypothermic, and barely arousable. Initial biochemistry revealed a thyroid stimulating hormone (TSH) of >100 mU/L and free thyroxine (FT4) level of 1.5 pmol/L which supported a diagnosis of myxoedema coma. She was resuscitated and commenced on liothyronine, levothyroxine, and hydrocortisone and some improvement was made. It became apparent that she was hiding and spitting out her oral levothyroxine including levothyroxine elixir. Given the need for prompt alternative control, we sought advice from international experts where intramuscular levothyroxine was recommended. She was managed from day 50 onwards with intramuscular levothyroxine 200 mcg once a week, which was subsequently increased to 500 mcg. Thyroid function normalized and she made continual cognitive and physical progress and was discharged to a rehabilitation hospital. Her intramuscular levothyroxine was stopped and she was subsequently restarted on oral levothyroxine, with a plan for on-going close monitoring of her thyroid function. This report highlights the potential to use intramuscular levothyroxine in individuals with severe hypothyroidism arising from poor compliance with levothyroxine treatment or other potential causes such as impaired absorption. [ABSTRACT FROM AUTHOR]