Quick Reference
- Full form
- Free Thyroxin Index (FTI, T7)
- Sample type
- Blood
- Fasting
- Not required
- Marker measured
- 1
- Report turnaround
- Next day
- Available at
- All locations
About Free Thyroxin Index (FTI, T7)
The Free Thyroxin Index estimates your active thyroid hormone level by adjusting your total T4 for protein binding effects, useful in situations where protein levels might otherwise distort a simple T4 reading.
No fasting is required, and results are available the next day.
How to Prepare
- No fasting required.
- No special preparation needed before your blood draw.
Frequently Asked Questions
What does the Free Thyroxin Index measure?
It estimates your active thyroid hormone level by adjusting total T4 for protein binding effects.
Do I need to fast before this test?
No fasting is required.
Why would my doctor order this instead of a simple T4 test?
It corrects for situations where protein levels might distort a simple T4 reading, giving a more accurate result.
Is this test part of a thyroid panel?
It can be ordered alongside other thyroid tests for a fuller picture of thyroid function.
How soon will my report be ready?
Next day.
Is home sample collection available?
Yes, in all City Care Lab service areas.
This page provides general health information and is not a substitute for medical advice. Speak with your doctor about your specific results and treatment.