Hypothyroidism, Treatment of

Hypothyroidism used to be regarded as a simple condition to treat, with adequacy of dose of thyroid hormones being judged more on the patient's satisfaction than on biochemical monitoring. As a result of the development of sensitive tests of thyroid function, there is now controversy about the correct form and amount of replacement therapy and whether biochemical evidence of overtreatment, as judged by a suppressed serum thyrotropin concentration, is a risk factor for the well-recognized complications of overt hyperthyroidism, namely atrial fibrillation and osteoporosis. Subclinical hypothyroidism is increasingly viewed as the mildest form of thyroid failure, and there is sense in starting thyroid hormone replacement sooner rather than later, particularly in those individuals who are positive for antithyroid peroxidase antibodies.