Affecting 2% of women and 0.2% of men, thyrotoxicosis describes excess circulating thyroid hormones. This can be due to increased production and secretion (hyperthyroidism) or the release of (thyroiditis) stored thyroid hormones. Subclinical or borderline hyperthyroidism may occur in between 0.5%-10% of adults.[⁷]

The most common form of thyrotoxicosis in the UK is Graves’ disease, an autoimmune condition, accounting for 60-80% of cases, most commonly appearing in women aged between 30 and 60. The autoimmune reaction produces thyroid-stimulating immunoglobulins (TSIs) which mimic TSH, resulting in excess thyroid hormones production.[^7,14]

Causes may be due to genetic predisposition triggered by factors such as stress, infection or pregnancy. Other risk factors associated with Graves’ disease include type 1 diabetes, rheumatoid arthritis and smoking.[¹⁴]

Typical symptoms include heat sensitivity and increased sweating, weight loss, increased appetite, fatigue, weakness, tremor, anxiety, restlessness, insomnia, mood changes, thirst, increased urination, and osteoporosis. Cardiovascular changes include hypertension and heartbeat irregularities.[^4,15]

Characteristic physical changes include:[^4,16,17]

·    -  skin changes on the shin (pretibial myxoedema):

·    -  bulging eyes (exophthalmos) due to an inflammatory response behind the eye sockets (ophthalmopathy);

·     - swollen digits and fingertip clubbing (acropachy).

Thyrotoxicosis occurs in only 0.01% to 0.02% of children but can severely affect them with long-term consequences. These include cardiovascular conditions and bone-related complications such as osteoporosis.[⁷]