Quest Diagnostics Thyroid Disorder Monitoring — Ongoing
Type
Blood Testing
Biomarkers
4
Duration
30 min
Results
48 hours
Measures key thyroid hormones to determine if hypothyroidism treatment is effective.
This test measures TSH and T4 levels in the blood to assess thyroid function and monitor the effectiveness of hypothyroidism treatment. It's a follow-up to the initial Thyroid Disorder Monitoring panel, used after treatment begins. Abnormal results may indicate hyperthyroidism or hypothyroidism, requiring medical attention. This panel does NOT test for thyroid peroxidase (TPO) antibodies.
Key Details
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
4The 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).
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.
A thyroid hormone; levels are measured to evaluate thyroid function.
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.
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+ $9.10 Physician Service Fee
- Category
- Diagnostic
- Sample Type
- Blood draw
- Duration
- 30 min
- Results
- 48 hours
Quest Diagnostics
QuestHealth offers accessible, on-demand health testing for individuals seeking quick and reliable diagnostic solutions.
