A goiter is an enlargement of the thyroid gland, and in Latin, guttur means throat. Goiters may occur because of too little production of thyroid hormone (hypothyroid) or too much production of thyroid hormone (hyperthyroid).

Iodine deficiency used to be the most common form of hypothyroidism causing goiters. It is common among the people living in the hills, where the iodine content of the soil is limited, due perhaps to soil erosion by continued rains, etc. More precisely, the disease is called endemic iodine deficiency goiter. Iodine deficiency does not allow the thyroid gland to produce the normal amount of iodine containing thyroid hormones. Iodide deficiency has become a rare form of hypothyroidism since iodized salt was introduced in the 1920's. 

Hypothyroidism is caused by an underproduction of thyroid hormone.  In addition to iodide deficiency, other causes include Hashimoto's thyroiditis which is an autoimmune disorder which attacks the thyroid gland, drug induced hypothyroidism from the heart anitarrhythmic medication amiodarone, as  well as lithium.  

Hyperthyroidism is due to an overproduction of the thyroid hormones from the thyroid gland.  The most common causes for hyperthyroidism include Grave's disease, which is also an autoimmune disorder effecting the thyroid gland, thyroiditis, which is an inflammatory reaction affecting the thyroid, and toxic adenomas, which are nodular growths of the thyroid gland which secrete excessive thyroid hormones. Thyroid cancer is much less common then benign thyroid nodules and can only be determined by imaging studies and biopsy of the nodule.

 Significant symptoms related to a thyroid goiter include and enlarging growth and swelling of the neck, difficulty swallowing, coughing, a tight feeling of the throat, and if there is any difficulty breathing, immediate medical evaluation is necessary.  Further evaluation of a solitary or multiple thyroid nodules include blood tests of thyroid hormone and thyroid stimulating hormone (TSH) levels, measurement of thyroid antibodies, ultrasound studies to determine if the nodules are solid or cystic, and radioactive thyroid scans to determine if the enlarged nodule has increased uptake of iodine.  Finally, biopsy or surgical removal of part or the entire thyroid gland may be necessary to relieve symptoms of shortness of breath or if the nodule is cancerous.

Treatments for a thyroid goiter depends on both the degree of enlargement of the gland, symptoms if any, thyroid hormone abnormalities, and the determination on whether there is cancer confirmed by the radioactive scans or biopsy.  Medications such as levothyroxine are commonly used for hypothyroidism and there are medications for goiter induced by hyperthyroidism as well.  Radioactive iodine is also sometimes used to treat the overactive thyroid gland. Surgery is needed if the thyroid nodule is felt to be cancerous or if the thyroid enlargement is causing severe shortness of breath.

Any abnormal growth or nodule around the neck requires evaluation by a medical professional.  Thyroid goiters caused by either hypo or hyperthyroidism is usually easily treatable with appropriate medications, and most people continue to live active and healthy lifestyles.