Thyroid panel
TSH
Also called Thyroid-stimulating hormone · measured in mIU/L
What it measures
The pituitary hormone that regulates thyroid output.
Why it is tracked
The first-line thyroid test. Thyroid dysfunction produces fatigue, weight change, hair loss and low libido — the same complaints that bring people to hormone and weight clinics — so excluding it early avoids treating the wrong problem.
What a provider considers
- Rises as thyroid output falls, which is counter-intuitive
- Interpreted with free T4 where abnormal
- Affected by acute illness and some medications
Reference ranges vary between laboratories and a single result rarely means much on its own. Interpretation depends on your symptoms, your other markers and the trend over time — which is what your provider reviews.