What Do High Thyroid Levels Mean?

The thyroid is a very small gland in front of the neck that converts iodine into the hormone needed to regulate the body's metabolism. Having high thyroid levels means that at the time the levels were assessed (through a blood test), the thyroid was producing too much thyroxine (T4) and/or triiodothyronine (T3), the two hormones that constitute the "thyroid hormone." Having high thyroid levels is indicative of an underlying health condition that results in the gland being overstimulated.


The effects of high thyroid levels is indicative of hyperthyroidism, of which there are several different underlying causes 2. But no matter what triggers high thyroid levels, the signs and symptoms that patients exhibit are fairly static. Because:

  • too much thyroid hormone means an increased metabolism
  • high thyroid symptoms include unexplained weight loss
  • nervousness
  • anxiety
  • heat intolerance
  • tremors
  • high blood pressure
  • an increased resting heart rate

Patients with high thyroid levels may have difficulty falling and staying asleep. When hyperthyroidism is advanced, patients might be short of breath and develop muscle weakness 2. Disorders that lead to hyperthyroidism often develop slowly, making this condition difficult for endocrinology and thyroid specialists to diagnose in its early stages, which is critical in the case of thyroid cancer 2.

Graves' Disease

Graves' disease is the most common form of hyperthyroidism that results in high thyroid levels 2. This condition is actually an autoimmune disorder that causes antibodies to "attack" the thyroid gland in much the same way antibodies cause the body to react to airborne allergens. Patients with Graves' disease produce too much thyroxine (T4). Sometimes, high thyroid symptoms associated with Graves' disease include the tissue behind the patient's eyes being affected too, causing pressure behind the orbital sockets.

Thyroid Nodules

Thyroid nodules can also cause high thyroid levels because too much T4 to be released into the body. Nodules are almost always benign in nature, not related to thyroid cancer, and result when lumps form in one lobe of the gland. Not all thyroid nodules will result in overproduction of T4, however.


Thyroiditis occurs when the thyroid gland becomes inflamed. This too can result in high thyroid levels. Some types of thyroiditis, such as:

  • subacute thyroiditis
  • result in an enlarged
  • painful thyroid gland
  • while other types of thyroiditis are painless

Thyroiditis is typically transient in nature and may not need extensive medical treatment.

Treating High Thyroid Levels

Patients suffering from high thyroid symptoms should see a physician experienced in endocrinology and thyroid disorders. High thyroid symptoms are usually treated with oral anti-thyroid medications that inhibit the production of the thyroid hormone, the most common being methimazole (Tapazole). Beta blockers are also given in conjunction with anti-thyroid medications to treat high blood pressure and slow down the heart rate. Hyperthyroidism symptoms begin to go away in about six weeks, during which time high thyroid levels resolve 2. Other treatments for hyperthyroidism include radioactive iodine, which is taken orally to "kill" the thyroid gland so that it can no longer produce thyroid hormone 2. Patients who opt for this treatment will become hypothyroid and require lifetime hormone replacement therapy. Only rarely will surgery to remove the thyroid be necessary. This option is for patients who have a poor response to anti-thyroid medication or radioactive iodine therapy.