Thyroid Health Blood Test

Concerned your thyroid isn't working correctly? Find out for sure.

Your thyroid is essential to your health and wellbeing. From how fast your heart beats to how quickly your body burns calories, your thyroid directly influences things as subtle as your mood and as vital as your fertility.

This test measures both thyroid-stimulating hormone (TSH) and Free T4 (thyroxine) to assess thyroid function and can screen for specific thyroid conditions, such as underactive thyroid (hypothyroidism) and overactive thyroid (hyperthyroidism).

TSH and T4 levels work interdependently (and often inversely) rising or falling in response to one another. For example, low T4 levels often cause TSH levels to rise signaling hypothyroidism, while high T4 levels often cause TSH to drop signaling

Sample Type

Blood

$84

Preparation

If you’re taking a supplement containing biotin (also called vitamin B7 or B8, vitamin H, or coenzyme R), commonly found in products promoting nail, skin, and hair health, it is recommended that you wait at least 72 hours from your last dose before sample collection.

What's Included

Thyroid Stimulating Hormone (TSH):

A hormone that stimulates the thyroid gland to produce T4 (thyroxine) and T3 (triiodothyronine), two hormones that play critical roles in controlling the body’s metabolism.

T4 (Thyroxine):

A hormone produced by the thyroid gland, in conjunction with Triiodothyronine T3, that is responsible for regulating body temperature, heart rate, and metabolism.

Why Consider This Test

Specific Thyroid Concerns

Tests that measure both TSH and T4 can be used together to screen for and help diagnose thyroid conditions, including hypothyroidism (under-active thyroid) and hyperthyroidism (an over-active thyroid).²

Female Health and Fertility

Women are five to eight times more likely than men to have thyroid problems. Hypothyroidism is a leading cause of difficulty in achieving and maintaining pregnancy.²

Proactive Prevention

Undiagnosed thyroid disease may put patients at risk for certain serious conditions such as cardiovascular diseases, osteoporosis, and infertility. Most thyroid conditions can be managed with medication.²

References

1. “Thyroid Stimulating Hormone (TSH).” Lab Tests Online, The American Association for Clinical Chemistry, www.labtestsonline.org/tests/thyroid-stimulating-hormone-tsh?gclid=Cj0KCQjw4qvlBRDiARIsAHme6ou6S5VEYTZWydE3z5j-0taZURMhSNPtt-iZ2FXrLTtqUQyN46rDsyIaAuwgEALw_wcB.
2. American Thyroid Association. “General Information/Press Room.” American Thyroid Association, www.thyroid.org/media-main/press-room/.

How To Get This Test

1. Purchase your tests

Shop for tests and pay online. We do not bill insurance.
An independent physician will review and approve your test requests; no doctor’s visit is required.

2. Visit a LabCorp location

We'll email you your lab requisition number. Bring this number and photo ID to a LabCorp location for sample collection. You can make an appointment or just walk in.

3. Access your results online

View your easy-to-read results online in your Pixel by LabCorp account. For certain results that require prompt attention, you will also be contacted by phone or mail.