TSH Thyroid Test
A TSH (thyroid-stimulating hormone) test checks how well your thyroid is working. A level that is too high or too low may point to an underactive or overactive thyroid (MedlinePlus). It is often included in a baseline workup, but it does not screen for the thyroid C-cell tumors described in the GLP-1 boxed warning. Cash prices ran $39 to $78 as of September 23, 2026.
What does a TSH test measure?
TSH is a hormone made by the pituitary gland that tells the thyroid how much thyroid hormone to make. A TSH test is used to find out whether the thyroid is making too much hormone (hyperthyroidism) or too little (hypothyroidism) (MedlinePlus).
How does TSH relate to the GLP-1 thyroid warning?
This is the part that confuses people most.
Semaglutide and tirzepatide carry a boxed warning because they caused thyroid C-cell tumors in rodents. It is not known whether they cause these tumors, including medullary thyroid carcinoma (MTC), in people. The drugs are not to be used by anyone with a personal or family history of MTC or with MEN 2 (Wegovy prescribing information, boxed warning) (Zepbound prescribing information, boxed warning).
C-cell tumors are a different issue from overall thyroid function, which is what TSH measures. The labels do not recommend TSH testing for this warning. They say routine monitoring of serum calcitonin or thyroid ultrasound is “of uncertain value” for early detection of MTC, and could lead to unnecessary procedures (Wegovy prescribing information, section 5.1). The labels ask clinicians to tell patients about symptoms of thyroid tumors, such as a lump in the neck, trouble swallowing, shortness of breath, or hoarseness that does not go away.
Why is TSH commonly ordered before a GLP-1, then?
Thyroid function tests are a common part of evaluating weight-related health in general. A 2023 clinical review on evaluating adults with obesity lists them among standard blood tests (Dobbie et al., 2023). The ADA lists TSH in the initial evaluation for people with type 1 diabetes specifically (ADA Standards of Care 2026, Section 4, Table 4.1). Whether it is needed for you is up to the prescriber.
How do I prepare for a TSH test?
MedlinePlus says you may need to stop certain medicines before the test, so tell the provider about everything you take (MedlinePlus). TSH itself does not usually require fasting, but if it is drawn with a lipid panel or CMP, follow the fasting instructions for those.
How much does a TSH test cost without insurance?
| Where | Test price | Required fee | Total | Link |
|---|---|---|---|---|
| Walk-In Lab | $35 | $6 | $41 | View at Walk-In Lab |
| Personalabs | $78 | None listed | $78 | View at Personalabs |
| HealthLabs.com | $39 | None listed | $39 | View at HealthLabs.com |
| Private MD Labs | $43 | None listed | $43 | View at Private MD Labs |
| Quest (questhealth.com) | $49 | $6 | $55 | View at Quest (questhealth.com) |
Prices last checked September 23, 2026 on each company's own website. Prices change often, and sales come and go, so confirm the price at checkout. Totals add one required fee per order. Not checked: Labcorp OnDemand (site unavailable on the check date).
Frequently asked questions
- Does a TSH test screen for the thyroid tumors mentioned in the GLP-1 warning?
- No. The boxed warning on semaglutide and tirzepatide is about thyroid C-cell tumors, including medullary thyroid carcinoma. TSH measures overall thyroid function. The prescribing information says routine calcitonin testing or thyroid ultrasound is of uncertain value for early detection of these tumors.
- Why is TSH on some GLP-1 lab lists, then?
- Thyroid function tests are a common part of evaluating weight-related health in general. A 2023 clinical review on evaluating adults with obesity lists them among standard blood tests. The drug labels do not list TSH as a required test.
- How much does a TSH test cost without insurance?
- Across the online providers we checked, a TSH test cost between $39 and $78 including any required fee. See the dated price table on this page.
Sources
- TSH (Thyroid-stimulating hormone) Test. MedlinePlus, U.S. National Library of Medicine. Checked September 23, 2026.
- WEGOVY (semaglutide) injection and tablets, Prescribing Information (revised 06/2026). Novo Nordisk / U.S. FDA. Checked September 23, 2026.
- ZEPBOUND (tirzepatide) injection, Prescribing Information (revised 08/2026). Eli Lilly / U.S. FDA. Checked September 23, 2026.
- Clinical evaluation of patients living with obesity (Dobbie LJ, Coelho C, Crane J, McGowan B). Internal and Emergency Medicine, 2023. Checked September 23, 2026.
- 4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Care in Diabetes 2026 (Table 4.1). American Diabetes Association, Diabetes Care 2026;49(Suppl 1):S61 to S88. Checked September 23, 2026.