Thyroid Stimulating Hormone (TSH) with Triple Stimulation Test (Serum/Plasma)
This test measures your body’s response to a controlled dose of thyroid-stimulating hormone (TSH) to evaluate how well your thyroid gland functions under different conditions.
["Assesses thyroid hormone production and potential thyroid dysfunction after stimulation."]
Key facts at a glance
- LOINC
- 40401-2
- Short code
- TSH pre Triple Bolus SerPl-aCnc
- Synonyms
- TSH pre Triple Bolus SerPl-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.4
- Ref high
- 4
- Critical range
- 0.1 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84443
- SNOMED
- 301343003
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Is the Purpose of This Test?
Your healthcare provider may order this test to check if your thyroid is producing the right amount of hormones, especially if you have symptoms like fatigue, weight changes, or unexplained issues with metabolism. The triple stimulation helps differentiate between conditions like hypothyroidism, hyperthyroidism, or pituitary dysfunction by testing responses to multiple doses of TSH.
How Is the Sample Collected?
A blood sample will be taken from a vein in your arm. You may feel a small pinch, but it usually doesn’t cause discomfort. The sample is drawn at baseline and after each dose of TSH is administered to measure hormone levels over time.
What Should You Expect Before the Test?
No special preparation is needed, but inform your provider about any medications (including supplements) you take, as they may affect results. Avoid smoking or caffeine for a few hours before the test, as they can influence hormone levels.
How Long Does It Take to Get Results?
Results are typically available within 1–3 business days after the test is completed. Your provider will discuss them with you during your follow-up visit.
Reference range
Adult: 0.4-4.0 mIU/LN/A
Take your thyroid medication after the blood draw if applicable. No fasting required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal results can help diagnose or monitor thyroid disorders, such as underactive (hypothyroidism) or overactive (hyperthyroidism) thyroids. The triple stimulation test helps pinpoint whether low TSH levels are due to a thyroid issue or a problem with the pituitary gland, which controls thyroid hormone production.
Short name
TSH Stimulation Test
Frequently asked questions
Why did my doctor order this test?
What do my results mean?
Can I take my thyroid medication before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy