Índice de T3/T4 Livre (FTI)
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
FTI
About this calculator
The T3/T4 Free Index (FTI) Calculator is a useful tool for healthcare professionals and patients who need to calculate the T3/T4 free index.
The FTI is calculated by multiplying the T4 level by the RT3U level and dividing by the value of 100. This formula helps understand the relationship between the levels of T3 and T4 in the body.
The T3/T4 Free Index is important for diagnosing and monitoring thyroid conditions, such as hypothyroidism or hyperthyroidism. When using this calculator, it is essential to consider common precautions, such as consulting a doctor to interpret the results.
Frequently asked questions
What is the T3/T4 Free Index (FTI)?
The FTI is an index that calculates the relationship between the levels of T3 and T4 in the body. It is important to understand the function of the thyroid gland.
Why is it important to calculate the FTI?
The FTI is important for diagnosing and monitoring thyroid conditions, such as hypothyroidism or hyperthyroidism. It also helps to understand the effectiveness of treatment with medications.
What are common precautions when using this calculator?
It is essential to consider the need to consult a doctor to interpret the results and understand the relationship between the levels of T3 and T4 in the body.
Can I use this calculator without consulting a doctor?
No, it is essential to consult a doctor to interpret the results and understand the relationship between the levels of T3 and T4 in the body.