Why is T4 (Thyroxine), Total important?

Total T4 reflects thyroid gland output. While useful for screening thyroid disorders, it's affected by protein levels (pregnancy, estrogen, liver disease). Free T4 is often preferred for accuracy. Total T4 remains useful when evaluated alongside TSH and protein status.

What are the symptoms of abnormal T4 (Thyroxine), Total levels?

High T4 (hyperthyroidism): Weight loss, rapid heartbeat, anxiety, tremor, heat intolerance, sweating, diarrhea, menstrual irregularities. Low T4 (hypothyroidism): Fatigue, weight gain, cold intolerance, constipation, dry skin, depression, slow heart rate.

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T4 (Thyroxine), Total

thyroid health

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Total T4 measures all thyroxine in the blood, including both protein-bound and free forms. T4 is the main hormone produced by the thyroid gland and is converted to the more active T3 in tissues.

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Total T4 reflects thyroid gland output
While useful for screening thyroid disorders, it's affected by protein levels (pregnancy, estrogen, liver disease)
Free T4 is often preferred for accuracy
Total T4 remains useful when evaluated alongside TSH and protein status

Total T4 measures all thyroxine in the blood, including both protein-bound and free forms
T4 is the main hormone produced by the thyroid gland and is converted to the more active T3 in tissues

High T4 (hyperthyroidism): Weight loss, rapid heartbeat, anxiety, tremor, heat intolerance, sweating, diarrhea, menstrual irregularities.
Low T4 (hypothyroidism): Fatigue, weight gain, cold intolerance, constipation, dry skin, depression, slow heart rate.

High T4: Graves' disease, toxic nodular goiter, thyroiditis, excessive thyroid medication, pregnancy, estrogen therapy.
Low T4: Hashimoto's thyroiditis, thyroid surgery/radiation, pituitary dysfunction, severe illness, certain medications.

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T4 (Thyroxine), Total

About T4 (Thyroxine), Total

Why T4 (Thyroxine), Total Matters

Symptoms of T4 (Thyroxine), Total

What Affects T4 (Thyroxine), Total Levels

How it works: 4 easy steps

Choose your tests

Quick & convenient testing

Clear, personalized results

Optimize your health

Our Comprehensive Panels

Explore Other Tests

Basophils

Apolipoprotein B

Nitrite

Monocyte-to-Lymphocyte Ratio (MLR)

Our Customers Says

Have questions?