You received your TSH blood test results but still need help determining if they fall under the normal range. Read this section to know if your results range between the TSH normal range.
What Does TSH Blood Test Results Mean?
The TSH test results tell you if your thyroid gland is making too much or too little thyroid Hormone. However, the test itself is not a conclusive answer; hence if there is a deviation of the TSH Levels in your bloodstream, your healthcare professional will order more specific thyroid blood tests.
What Is TSH Test Normal Range?
A TSH level between 0.4 and 4.0 milli-international units per liter (mIU/L) is considered within the normal range if you have no history. But, if you are already undergoing treatment for any existing thyroid disorder, then the normal range would be 0.5 to 3.0 milli-international units per liter.
Normal level without any thyroid history
0.4 and 4.0 (mIU/L)
Normal level if undergoing treatment
0.5 to 3.0 (mIU/L)
What Medical Conditions Can Cause High TSH Levels?
A value above the normal range usually indicates that the thyroid is underactive. This indicates hypothyroidism. When the thyroid isn’t producing enough hormones, the pituitary gland releases more TSH to try to stimulate it.
Here are the medical conditions that can cause high TSH levels:
- Subclinical hypothyroidism
- Hashimoto's thyroiditis
- Thyroid gland dysfunction
- Medications ( lithium, amiodarone, and some antipsychotics)
- Pituitary or hypothalamic disorders
- TSH-secreting pituitary adenoma
What Medical Conditions Can Cause Low TSH Levels?
A value below the normal range means that the thyroid is overactive. This indicates hyperthyroidism. When the thyroid produces too many hormones, the pituitary gland releases less TSH.
Here are the medical conditions that can cause low TSH levels:
- Pituitary or hypothalamic dysfunction
- Secondary or tertiary hypothyroidism
- Sheehan syndrome
- Medications ( glucocorticoids, dopamine agonists, and somatostatin analogs can suppress TSH production)