Question 1

What's included in the Complete Thyroid Panel?

Accepted Answer

Five tests: [TSH](/tests/tsh) (screening), [Free T4](/tests/free-t4-test) (active circulating thyroxine), [Free T3](/tests/free-t3) (the most metabolically potent form), [Reverse T3](/tests/reverse-t3) (inactive 'brake' form), and [TPO Antibodies](/tests/tpo-antibodies) (autoimmune marker). Together they distinguish primary vs central hypothyroidism, T3 toxicosis, autoimmune cause, and impaired peripheral conversion.

Question 2

How is this different from just TSH?

Accepted Answer

[TSH](/tests/tsh) alone catches most primary thyroid disease, but misses central (pituitary) cause, T3 toxicosis, conversion problems, and silent autoimmune thyroiditis. Thyroid Complete catches all of those. If you have classic thyroid symptoms with a 'normal' TSH, this panel is the right next step.

Question 3

What does Reverse T3 add?

Accepted Answer

[Reverse T3](/tests/reverse-t3) is the inactive form your body produces under stress, illness, or caloric restriction. Elevated rT3 with normal [TSH](/tests/tsh) and [Free T4](/tests/free-t4-test) can indicate stress-induced 'cellular hypothyroidism' or impaired T4-to-T3 conversion — explaining symptoms that the standard tests miss. Mainstream endocrinology is skeptical; functional medicine relies on it heavily.

Question 4

What do TPO Antibodies indicate?

Accepted Answer

Positive [TPO Antibodies](/tests/tpo-antibodies) suggest autoimmune thyroid disease (Hashimoto's), the most common cause of hypothyroidism in the US. They can be elevated for years before TSH abnormalities appear — useful for risk-stratifying and timing repeat TSH monitoring.

Question 5

How much does the Complete Thyroid Panel cost without insurance?

Accepted Answer

On TestWell, the Complete Thyroid Panel is $109.99. Ordering the same 5 tests separately would be about $135. Quest Direct lists comparable bundles at $195, walk-in hospital labs typically bill $400-600 for the same biomarkers without insurance.

Question 6

Do I need to fast?

Accepted Answer

No fasting required for thyroid tests. Draw at the same time of day for serial monitoring (TSH has a mild circadian rhythm), and at least 4 hours after your levothyroxine dose if on thyroid replacement therapy.

Question 7

Should I add Thyroglobulin antibodies?

Accepted Answer

Optional — about 5% of Hashimoto's patients are TPO-negative but Thyroglobulin-positive. The standalone [Thyroid Antibodies](/tests/thyroid-antibodies) bundle includes both. If you've already tested TPO-positive, adding Thyroglobulin Ab rarely changes management.

Question 8

How often should I retest?

Accepted Answer

Annually if you have known thyroid disease that's well-managed. Every 6-8 weeks when starting or adjusting levothyroxine. Every 3 months in pregnancy or postpartum. Once for baseline if you're TPO-positive but euthyroid.

Complete Thyroid Panel

About This Panel

Clinical Use

Who Should Order This

Helps Evaluate

Tests Included in This Panel

Preparation Instructions

Preparation Instructions

Frequently asked questions

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