Thyroxine (T4), Total Blood Test

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Feature	Labcorp	Quest Diagnostics
Price	Coming soon	$5.99
Results in	—	~5 business days
Sample type	—	Blood Serum
Require fasting	—	No

About the test

This test is crucial for diagnosing thyroid conditions such as hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid). By measuring the total level of thyroxine (T4) in the blood, it helps in understanding thyroid function and identifying potential issues.

Who might consider it:

This test is typically ordered for individuals showing symptoms of thyroid dysfunction.

Symptoms of Hypothyroidism:

Fatigue
Weight gain
Cold intolerance
Dry skin
Constipation
Depression

Symptoms of Hyperthyroidism:

Weight loss
Heat intolerance
Nervousness
Insomnia
Hand tremors
Irregular heartbeat

Included biomarkers & Reference ranges

Biomarker	Reference range
T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.	4.5–12 µg/dL
Free T4 Index (T7) Free Thyroxine Index — a calculated estimate of free T4 thyroid hormone, adjusting total T4 for binding protein levels.	—

Reference ranges vary by lab, age, and sex (M/F). Your report shows your exact range. Click any biomarker to see its optimal range and what your results mean.

How it works

1. Order online No referral or insurance
2. Get a requisition By email in 24–72 hours
3. Visit a draw center Bring a matching photo ID
4. Get results Securely by email

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Consultations

Not sure how to read your results? We can help.

Schedule a consultation with a Hormunity specialist. We’ll walk through every marker, interpret what it means for you, and map out the next steps for your care.

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