Magno
Thyroid
Free T4 on TRT
What the number means, why it moves on a protocol, and how it sits with related markers.
What it is
Free T4 is the storage form of thyroid hormone, made by the gland and converted to T3 in tissue. It moves slowly and shows what the thyroid itself is producing.
The range
How to read the lab range
Lab range roughly 0.8 to 1.8 ng/dL (12 to 22 pmol/L). Low with a high TSH is hypothyroidism; low with a low TSH is a pituitary or medication story.
Why it moves on a protocol
- Thyroid disease.
- T3 medication lowers it because the gland stops making its own.
How Magno reads it
Magno keeps every test on one line, against your lab's range, with the change since last time. Pro explains it in plain words. Get Magno for iPhone.
Read yours
Drop your lab PDF or a photo and get every marker explained in plain words. Free, no account, your file never leaves your browser. Track it in the iPhone app to see the change since your last test.
Questions people ask
Is free T4 read on its own?
Rarely. It makes sense next to TSH and free T3.
Related markers
Not medical advice
This explains what the number is and why it moves. It is not medical advice; decisions belong to you and your clinician.