Management of hypothyroidism in adultsBMJ 2008; 337 doi: https://doi.org/10.1136/bmj.a801 (Published 28 July 2008) Cite this as: BMJ 2008;337:a801
- Bijay Vaidya, consultant endocrinologist and honorary senior clinical lecturer1,
- Simon H S Pearce, professor of endocrinology and honorary consultant physician2
- 1Department of Endocrinology, Royal Devon and Exeter Hospital, Exeter EX2 5DW, and Peninsula Medical School, Exeter
- 2Endocrine Unit, Royal Victoria Infirmary and Newcastle University, Newcastle upon Tyne
- Correspondence to: B Vaidya
Hypothyroidism is one of the commonest chronic disorders in Western populations. In the United Kingdom, the annual incidence of primary hypothyroidism in women is 3.5 per 1000 and in men 0.6 per 1000.1 During 2006 12 million prescriptions for levothyroxine (50 μg or 100 μg tablets) were dispensed in England, equivalent to about 1.6 million people taking long term thyroid replacement therapy, about 3% of the population.2 The management of hypothyroidism is generally considered straightforward and is mostly carried out in primary care in the UK. Cross sectional surveys of patients taking levothyroxine have, however, shown that between 40% and 48% are either over-treated or under-treated.3 4 Furthermore, a small but significant proportion of patients continue to feel unwell despite taking levothyroxine.5 This review discusses current approaches in the management of hypothyroidism in adults.
Sources and selection criteria
We searched PubMed and the Cochrane Library databases for the keywords hypothyroidism and thyroxine. We identified further references from the original articles and recent review articles. We studied articles only in the English language, and gave priority to those published in the past 10 years and those reporting randomised controlled trials.
In adults with newly diagnosed hypothyroidism who are under 60 and without ischaemic heart disease it is safe and efficient to start on a full replacement dose of levothyroxine
Levothyroxine replacement dose is related to body mass; a daily dose of about 1.6 μg levothyroxine/kg body mass is adequate replacement for most adults (equivalent to 100 μg daily or 125 μg daily for an average size woman or man, respectively)
Elderly people and those with ischaemic heart disease should start on a small dose of levothyroxine, and the dose increment should be gradual
Current evidence does not support a clinical benefit from the use of a combination of levothyroxine and liothyronine …