A diagram of the thyroid gland with a text bubble saying what is thyroid hormone conversion?

Normal Thyroid Physiology When we refer to ‘thyroid hormones’ we are talking about T3 and T4. They are the ones the thyroid gland secretes. T4 is more stable in the blood and better for transport around the body; T3 is more biologically active. Of the thyroid hormones produced, 85-90% is T4 and 10-15% is T3.…

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thyroid gland with an arrow over top and text bubble saying what is hypothyroid disease?

Hypothyroidism is the term used for abnormally low activity of the thyroid gland. Since the thyroid gland serves so many functions, signs and symptoms are varying and can affect many aspects of human health. Hypothyroidism is diagnosed by signs and symptoms, and confirmed with blood tests. It affects about 1 in 4,000 newborns and approximately…

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skeleton with thyroid gland in the background, and bottles of thyroid medications in the foreground with text bubble saying confusing thyroid blood work with thyroxin medications

Thyroid medications (such as Eltroxin and Synthroid) are some of the most prescribed medications in the world. Patients taking these medicationss often undergo routine blood work to track the progress of their hypothyroidism. Often times, patients taking thse thyroxin based medications have blood work that doesn’t make sense based on their symptoms. This article will…

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doctor confused by thyroid blood work

Normal Lab Testing Thyroid Function Tests (TFTs) are among the most commonly requested lab investigations. For most of the population, interpreting the lab work is fairly straightforward when we look at a combination of TSH, T4 and perhaps T3. Learn more about the routine lab work here. For a quick review of Basic Thyroid Anatomy…

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Man palpating his neck with thyroid gland superimposed on throat and text bubble saying confusing thyroid blood work: non-thyroidal illness

When your doctor assesses or treats your thyroid function, they will usually rely on blood work. In a lot of patients suffering from hypothyroidism, blood test results are confusing, and don’t follow the expected findings; one cause is non-thyroidal illness. Normal Testing Usually, testing is straightforward and results align with symptoms. In cases of hypothyroidism, we…

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Skeleton with thyroid gland and text bubble saying a review of healthy thyroid function: anatomy and physiology

This introductory article is one of many in-depth articles on thyroid function and focuses on normal thyroid anatomy and physiology. Learn more about hypothyroid, hyperthyroidism and testing by clicking the links. Basic Physiology and Anatomy The most important anatomical structures are shown in the image below: The hypothalamus creates a hormone called thyrotropin-releasing hormone (TRH).…

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Vials of blood held in a gloved hand with text bubble saying is TSH testing enough?

In ‘ideal’ thyroid physiology, a patient’s symptoms would be reflected in their blood work. As doctors, we learn low TSH is associated with hyperthyroidism and high TSH is associated with hypothyroidism. For a full recap on normal thyroid physiology, click here. Usually, thyroid lab test results match the symptoms. Ideal Situations Thyroid Stimulating Hormone (TSH)…

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thyroid gland with arrow pointing upwards and text bubble saying what is hyperthyroid disease?

Hyperthyroidism is the abnormally high activity of the thyroid gland. Since the thyroid gland serves so many functions, signs and symptoms are varying and can affect many aspects of human health. Hyperthyroidism is diagnosed by signs and symptoms and confirmed with blood tests and sometimes scans. It affects approximately 2% of women and 0.2% of…

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