The pharmacological management of hypothyroidism

Hypothyroidism is a condition characterised by the biochemical and clinical manifestations of deficient thyroid hormone concentrations. 1 Worldwide, the most common cause of this condition is iodine deficiency. In cases where iodine deficiency is not the cause, the most common causes of hypothyroidism are Hashimoto’s thyroiditis, thyroidectomy and radioactive iodine treatment. 2 Apart from thyroid gland pathology (primary hypothyroidism), hypopituitarism (secondary hypothyroidism) should also be considered. 2 Autoimmune hypothyroidism occurs at a mean annual rate of 4 per 1 000 women and 1 per 1 000 men. 2 The onset of hypothyroidism is usually insidious, and patients may only become aware of symptoms after optimal thyroid hormone replacement. Typical signs include a puffy face, oedematous eyelids, non-pitting pretibial oedema, dry, brittle hair, alopecia, thinning of the outer third of the eyebrows, pallor and retarded nail growth. 2 Goiter is sometimes the presenting symptom in Hashimoto’s thyroiditis, but typical symptoms like fatigue, dry skin, hair loss, constipation, cold intolerance and weight gain may also be present. The aim of therapy is to improve symptoms, normalise serum thyroid-stimulating hormone (TSH), reduce the goiter size and to avoid overtreatment. 3,4