What does reverse T3 tell you?

The Reverse T3 (RT3) test measures the inactive form of the hormone T3 or Triiodothyronine. Triiodothyronine is one of two major hormones produced by the thyroid (the other is T4, or thyroxine). Under normal conditions, the body converts T4 to T3 and RT3 in specific ratios.

What should your reverse T3 level be?

RT3 can be measured by a blood test. A level below 250 pg/ml (10 to 24 ng/dL) is considered normal.

What does it mean when your reverse T3 is elevated?

If your labs show a high reverse T3 level this means that you are converting most of your T4 into reverse T3. Reverse T3 is an isomer of T3. If you recall T3 is the most active form of thyroid and it is converted from T4 as needed.

What are the symptoms of high reverse T3?

Reverse T3 causes fatigue, difficulty losing weight, brain fog, muscle aches and all the other symptoms of hypothyroidism.

When do you order reverse T3?

Reverse T3 (rT3) This is often ordered in conjunction with a T4 test because it’s a hormone produced from your T4’s metabolism. If you’re experiencing chronic stress, depression, brain fog, anxiety, weight fluctuations or hair loss, your doctor may recommend this test for you.

Does T3 cause weight gain?

According to Dr. Kitahara, if someone has low thyroid function, their TSH is high, and the thyroid hormones known as T3 and T4 are low—and weight gain often occurs. If someone has an overactive thyroid or hyperthyroidism, TSH is usually low, the T3 and T4 are high, and weight loss occurs.

Why do doctors not test for T3?

Doctors don’t usually order the T3 test if they suspect hypothyroidism, or an underactive thyroid. Other tests can better spot this thyroid issue. The T3 test can also help your doctor identify thyroid cancer and other uncommon conditions that can affect your thyroid.

Why do doctors not test reverse T3?

There is a second T3 test — known as the “free T3” test — that looks for only certain types of T3 hormone in your blood. But, doctors usually don’t order this test because the results aren’t as helpful.

Is high reverse T3 bad?

Reverse T3 is generally considered to have little biological activity, but it has been linked to several health conditions. For example, one older study of 32 patients with depression found that higher rT3 levels may be associated with worse depression symptoms [55].

What causes high reverse T3 levels?

Prolonged stress and toxicity are the major causes of reverse T3 dominance. Unrelenting stress results in high levels of cortisol , the main hormone released by the adrenal glands in response to stress.

Is high T3 a sign of reverse T3?

Reverse T3 is sort of a hibernation hormone, in times of stress and chronic illness, it lowers your metabolism. Many people will have normal thyroid lab tests, but if they have high Reverse T3, they will feel like they have hypothyroidism . Lab Reference Range: 8-25 ng/dL

What is the optimal range for reverse T3?

Reverse T3 (rT3): This test measures the amount of reverse T3 that is produced. The production of rT3 typically takes place in cases of extreme stress, such as major trauma, surgery or severs chronic stress. Reverse T3 laboratory range is 90 to 350 pg/ml. Reverse T3 functional or optimal range is 95 to 345 pg/ml.

When to take T3 before blood test?

If you have had a recent injection for another health matter that your doctor does not know about, it may be beneficial to wait 1-2 weeks before having the T3U blood test performed. The T3 uptake blood test is useful in circumstances where a suspected thyroid issue may be causing bothersome signs and symptoms.