Conditions and diseases


Symptoms and causes

Symptoms and causes

What is it?

Hyperthyroidism is a benign disorder where the thyroid produces too many hormones.


This can lead to a variety of symptoms: nervousness, trembling, hot flushes, palpitations, sweating, changing appetite, changes in bowel movement patterns and changes in bodyweight. In the long term, this negatively affects the heart (heart rhythm disturbances such as atrial fibrillation) and bone density (osteoporosis).

The thyroid may be overactive because it is enlarged or because it contains an overactive lump (so-called ‘hot nodules’ on thyroid scintigraphy). Sometimes the thyroid is overactive due to a disturbance of the immune system, for instance autoimmune disorder because of Graves’ disease.

Sometimes the thyroid is not overactive yet, but we can tell from blood tests that there is a tendency to overproduce hormones (subclinical hyperthyroidism). In vulnerable or elderly patients this may be a reason to treat the thyroid with radioiodine therapy, to avoid heart rhythm disturbances.

Diagnosis and treatment

Diagnosis and treatment

Hyperthyroidism can be treated with iodine-131.

Latest publication date: 15/05/2024