15.02.1 Hypothyroidism

Congenital Hypothyroidism (often called cretinism) is most common preventable cause of mental retardation. Hypothyroidism, which when it is severe is known as myxedema) is the most common disorder of thyroid function and is most often due to iodine deficiency, and is also known as primary hypothyroidism). Some drugs cause hypothyroidism (e.g. amiodarone, which is an iodine containing medicine of similar structure to the thyroid hormones). The symptoms of hypothyroidism are calorigenic such as a low basal metabolic rate low, decreased body temperature, and weight gain. There are also central nervous system effects, which in the child, are mental and growth retardation, and in the adult, mental dulling, depression, memory impairment. On the cardiovascular system, in hypothyroidism there is decreased activity of sympathetic nervous system with low heart rate and heart pumping, leading to low blood pressure.

Treatment of hypothyroidism is to use iodated table salt as prevention, which promotes the synthesis of the thyroid hormones. In hypothyroidism, replacement therapy with thyroxine is used as treatment.