What is a good T4 free range?

In adults, normal levels of total T4 range from 5–12 micrograms per deciliter (mcg/dl) of blood. Normal levels of free T4 range from 0.8–1.8 nanograms per deciliter (ng/dl) of blood.

What does it mean if free T4 is high?

High levels of any of these tests (total T4, free T4, or free T4 index) may indicate an overactive thyroid, also known as hyperthyroidism. Low levels of any of these tests (total T4, free T4, or free T4 index) may indicate an underactive thyroid, also known as hypothyroidism.

What happens if your T4 levels are low?

Extremely low levels of thyroid hormone can cause a life-threatening condition called myxedema. Myxedema is the most severe form of hypothyroidism. A person with myxedema can lose consciousness or go into a coma. The condition can also cause the body temperature to drop very low, which can cause death.

What is a normal free T4 level for a woman?

Free T4 (FT4) level: FT4 test may be a more accurate way to determine thyroid function because, unlike total T4, free T4 level is not affected by the binding proteins. Normal FT4 level falls in the range of 0.7 to 1.9 ng/dL (nanogram/deciliter).

Which is more important TSH or free T4?

A 2020 review article in the prestigious journal Thyroid suggests that we may want to pay more attention to free T4 levels in assessing a patient’s clinical thyroid status. TSH is the controlling hormone for the release of T4 and T3 from the thyroid gland.

What is a dangerously high T4 level?

9 and 2.4 nanograms per deciliter. Total T4 tends to vary more with age. An abnormally high T4 level may indicate hyperthyroidism, thyroiditis, or goiter. It may lead to additional tests for Graves’ disease.

Can low T4 cause weight gain?

Unraveling the Thyroid Cancer-Obesity Links 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.

How do you treat low T4 levels?

The easiest and most effective treatment is simply taking a thyroid hormone pill (levothyroxine) once a day, preferably in the morning. This medication is a pure synthetic form of T4 which is made in a laboratory to be an exact replacement for the T4 that the human thyroid gland normally secretes.

What are the symptoms of high free T4?

As its name suggests, hyperthyroidism occurs when your body makes too much of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), and becomes overactive. If you have hyperthyroidism, you may experience a fast heartbeat, increased appetite, anxiety, sensitivity to heat, or sudden weight loss.