Information Living with thyroid disorders Hyperthyroidism - symptoms, diagnosis and treatment options Hyperthyroidism symptoms Hyperthyroidism leads to an increase in the body’s metabolism. In children and young people, the most obvious symptoms can be weight loss and rapid growth in height. There is a long list of other symptoms and signs associated with hyperthyroidism although not everyone will have all of them. These include: heart palpitations or a racing heartbeat sweating, not being able to stand heat, being intolerant of warmth and warm conditions tiredness nervousness and irritability shakiness a rapid pulse mood swings or aggressive behaviour loose bowel movements weak muscles warm, moist hands difficulty concentrating and sitting still thirst itchiness an enlarged thyroid gland (a goitre) Symptoms can come on very quickly – within the space of a few days or weeks – or may develop over a long period of time. Occasionally children with Graves’ disease may also develop thyroid eye disease (TED). This is usually quite mild in children. Hyperthyroidism diagnosis Hyperthyroidism is diagnosed through a physical examination and blood tests. If a blood test shows that your child’s TSH level is below the reference range and their T4 blood level is above the reference range, this usually indicates an over-active thyroid. Another blood test can measure the antibody levels in the blood to find out whether or not it is Graves’ disease that has caused the over-active thyroid so that it can be treated correctly. The doctor may also scan your child’s thyroid. Hyperthyroidism treatment options Treatment depends on the cause of the hyperthyroidism and how severe it is. Therefore it is important to identify the cause. There are three types of treatment available for hyperthyroidism: antithyroid drug therapy surgery radioactive iodine If your child has viral thyroiditis the hyperthyroid phase of the disease normally settles down without treatment.