What Are the Causes of Increased TSH Levels?

TSH is the thyroid stimulating hormone. In adults, the normal range for TSH is a lab value between 0.4 and 4.5 mIU/L (milli-international units per liter); however, the American Association of Clinical Endocrinologists recommends that 3.0 be considered the high end on the TSH range.

Hypothyroidism

• Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormone. This signals the pituitary gland to produce more TSH. If thyroid hormones remain at low levels, the body will continue to produce TSH, leading to elevated levels.

Medications

• Lithium and Amiodarone are two medications that suppress the level of thyroid hormone, which leads to an elevated TSH level. Other medications that can rarely cause elevations are chemotherapy drugs, antidepressants and drugs that treat epilepsy.

Iodine

• In adults who were not deficient in iodine, elevated TSH levels were discovered when the iodine intakes were between 1700 and 1800 mcg/day, according to the Linus Pauling Institute.

Detection

• TSH levels can be evaluated by performing a blood draw and sending it for laboratory analysis.

Treatment

• For hypothyroidism, a drug called Synthroid can administered. Lowering your intake of iodine if it is excessive or switching to more thyroid-friendly medications can also aid in correcting elevated TSH levels.