Below the range
Common causes of a low Free Triiodothyronine (Free T3)
- Hypothyroidism
- Euthyroid sick syndrome
Looking for the other direction? See what causes a high Free Triiodothyronine (Free T3).
All tests · Thyroid Function · Free Triiodothyronine (Free T3)
Below the range
What causes a low Free Triiodothyronine (Free T3)?
Normal range 2.3-4.2 pg/mL (3.5-6.5 pmol/L SI). Specimen: Serum. See the full Free Triiodothyronine (Free T3) reference page for critical values and nursing considerations.
What is the normal range for Free Triiodothyronine (Free T3)?
The standard teaching reference range for Free Triiodothyronine (Free T3) is 2.3-4.2 pg/mL in conventional units, or 3.5-6.5 pmol/L in SI units. This value is measured in serum.
| Specimen | Serum |
|---|---|
| Conventional range | 2.3-4.2 pg/mL |
| SI range | 3.5-6.5 pmol/L |
| Panel | Thyroid Function |
Full details, including nursing considerations, on the Free Triiodothyronine (Free T3) normal range page. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.
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