A swelling in the neck due to enlargement of the thyroid gland

  • Age, gender, genetics, and lifestyle as risk factors depend on the cause

If the thyroid gland becomes enlarged, it causes a swelling to appear in the neck. This swelling is known as a goitre. A goitre can range in size from a barely noticeable lump to a swelling the size of a grapefruit. In rare cases, a very large goitre may press against the oesophagus and trachea (windpipe) in the neck, which can cause difficulty in swallowing and breathing.

What are the causes?

The thyroid gland may enlarge without any disturbance of its function at certain times, particularly at puberty and during pregnancy. Disorders that may be associated with goitre include hyperthyroidism, hypothyroidism, thyroid nodules, and certain types of thyroiditis. Goitre is a known side effect of drugs such as lithium (see Mood-stabilizing drugs), which is used to treat bipolar affective disorder. Iodine deficiency may also be a cause of goitre, although this is extremely rare in developed countries. Rarely, goitre is due to thyroid cancer.

What might be done?

Your doctor will examine your neck to assess the size and shape of the thyroid gland. A blood sample may be taken to measure your thyroid hormone levels, and ultrasound or radionuclide scanning may be performed to look at the thyroid. Needle aspiration of the thyroid gland may be performed for a more precise diagnosis.

Treatment with surgery, radioactive iodine, or antithyroid drugs (see Drugs for hyperthyroidism) is sometimes successful in shrinking a goitre in people with hyper-thyroidism. Surgery may also be necessary if breathing or swallowing is obstructed or if thyroid cancer is suspected. A small goitre that has no effect on thyroid function may not need treatment and may decrease in size or disappear completely with time.


This swelling in the neck, called a goitre, is due to enlargement of the thyroid gland. Most goitres are painless.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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