A goitre (sometimes spelled "goiter") is a swelling of the thyroid gland that causes a lump in the front of the neck. The lump will move up and down when you swallow.
The thyroid gland is a small butterfly-shaped gland in the neck, just in front of the windpipe (trachea).
It produces thyroid hormones, which help regulate the body's metabolism, the chemical processes that occur in the body.
The size of a goitre can vary from person to person. In most cases, the swelling is small and does not cause any symptoms.
In more severe cases, symptoms may include:
See your GP if you think you have a goitre. They'll examine your neck to see whether your thyroid gland is swollen.
The GP may also request a thyroid function test to see how well your thyroid gland is working.
A thyroid function test measures the level of certain hormones in your blood.
It can show whether you have an underactive or overactive thyroid, both of which are associated with goitre.
If necessary, you may be referred to a specialist in hospital for further tests or treatment.
The treatment for a goitre depends on the underlying cause.
If the goitre is small and not causing any problems, a wait-and-see approach is usually recommended.
Other possible treatments include radioiodine treatment and thyroid surgery.
Although most goitres are non-cancerous, it's estimated that in 1 in 20 cases they may be a sign of thyroid cancer.
A goitre can have several possible causes, including:
Anyone can develop a goitre, but the chances increase with age. Women are also more likely to develop a goitre.
There are 2 main types of goitre: