Quest Diagnostics Thyroid Disorder Monitoring — Initial
Type
Blood Testing
Biomarkers
5
Duration
30 min
Results
48 hours
Measures key hormones in thyroid function for those diagnosed with a thyroid disorder.
This test measures the levels of thyroid stimulating hormone (TSH), thyroxine (T4), and thyroid peroxidase (TPO) antibodies in your blood. These markers help determine whether your treatment plan is working properly to manage your thyroid disease. This test is intended as a follow-up for those being provided a treatment option after taking our Thyroid Function Test. If your test results are abnormal, an independent physician may be able to provide you with treatment options.
Key Details
- Biomarkers
- 2–7 thyroid markers
- Fasting Required
- No
- Sample Type
- Blood draw
- Turnaround
- 24–48 hours
- Common Use
- Thyroid function, autoimmune screening
Who Is This For?
Anyone experiencing unexplained fatigue, weight changes, hair loss, cold sensitivity, or mood disturbances. People with a family history of thyroid disease or autoimmune conditions. Women planning pregnancy, as thyroid function is critical for fetal brain development. Anyone who has had a 'normal' TSH result but still suspects thyroid dysfunction.
What's Included
Preparation Required
No fasting required for a standalone thyroid panel. If you take thyroid medication (levothyroxine/Synthroid), take your dose after the blood draw, not before — taking it beforehand can temporarily spike T4 levels and skew results. Morning testing is recommended for the most consistent TSH readings, as TSH follows a circadian rhythm and peaks overnight.
Biomarkers Tested
5The primary screening test for thyroid function. TSH is produced by the pituitary gland to regulate thyroid hormone production. High TSH indicates an underactive thyroid (hypothyroidism), while low TSH suggests an overactive thyroid (hyperthyroidism).
A thyroid hormone; levels are measured to evaluate thyroid function.
Antibodies against thyroid peroxidase, an enzyme essential for thyroid hormone production. Positive TPO antibodies indicate autoimmune thyroid disease, most commonly Hashimoto's thyroiditis, even before symptoms or TSH changes appear.
The unbound, active form of the main thyroid hormone T4. Free T4 directly reflects thyroid gland output and is used alongside TSH to diagnose and monitor thyroid disorders.
The active form of thyroid hormone responsible for regulating metabolism, energy, and body temperature. Free T3 is converted from T4 in tissues and is three to four times more potent than T4.
+ $9.10 Physician Service Fee
- Category
- Diagnostic
- Sample Type
- Blood draw
- Duration
- 30 min
- Results
- 48 hours