What Does a High TSH Mean?

The pituitary gland produces a hormone called thyrotropin or thyroid-stimulating hormone (TSH). TSH stimulates the thyroid gland to produce hormones of its own. TSH levels in the blood indicate whether the thyroid gland is functioning properly. High TSH levels are usually a sign of an underactive thyroid gland.

Indicators

• A blood test result with TSH levels above 2.0 mIU/L may be an indicator of early hypothyroidism. The condition should be monitored by a doctor, and additional blood tests may be required.

Significance

• High TSH levels indicate a lack of communication between hormones produced by the pituitary gland and the thyroid gland, resulting in hypothyroidism, or slowing of thyroid activity.

Signs

• Signs of high TSH levels indicating hypothyroidism may include sluggishness, weight gain, constipation, cold hands and feet, dry skin and memory loss.

Treatment

• Synthetic thyroid hormones are used to treat high TSH when the thyroid gland is not producing enough of its own hormones. Thyroid hormone treatment increases thyroid hormone levels in the blood and returns high TSH levels to normal.

Considerations

• Some people with high TSH levels still have normal levels of thyroid hormones in their blood. This condition, known as subclinical hypothyroidism, often leads to hypothyroidism.