In the first of a short series of articles on endocrinology, H S Randeva and P M G Bouloux explain the various manifestations of thyrotoxicosis and tell you how to diagnose and treat it
- By: H S Randeva, P M G Bouloux
Thyrotoxicosis or hyperthyroidism is the clinical syndrome caused by an excess of circulating free thyroxine and free triiodothyronine, or both. It is common, affecting about 2% of women and 0.2% of men.
Of the causes of thyrotoxicosis (box 1), Graves' disease is the most common (70-80%); toxic thyroid adenoma, toxic multinodular goitre, and subacute thyroiditis account for most of the remainder. Surreptitious overdosing (factitious thyrotoxicosis) is occasionally seen.