TriIodothyronine Free

Test Results & Interpretations

Overview of TriIodothyronine Free

Test Description

Also known as FT3 or total triiodothyronine test, it is used to measure the unbound and free T3 levels present in the bloodstream of the body. The test assesses the functioning of the thyroid gland to help diagnose hyperthyroidism, hypothyroidism or other thyroid disorders.

Why Get Tested

The FT3 test is used to evaluate the thyroid gland function, to diagnose disorders like hyperthyroidism which has symptoms like nervousness, tremors, insomnia, weight loss and swollen eyes. It also diagnoses hypothyroidism with symptoms like weight gain, slow metabolism, dry skin, constipation and fatigue. FT3 test also monitors the effectiveness of the thyroid treatment.


  • Do not eat or drink anything other than water for 8-12 hours before the test.

What Results of TriIodothyronine Free mean?


The results show either excessively high or low levels of free T3 in the blood samples. The normal range for free T3 is from 1.8 to 5.4 mcg/dl for men and women of all age groups.

Provided By




Established in 1995, Lifecare is the country's premier full-service diagnostic center with laboratory, providing expertise in imaging and digital pathology services. Our integrated diagnostic services help doctors personalize patient care to optimally treat disease and maintain health and wellness. We are committed to providing only the highest level of testing quality and service and working with you to provide unique solutions to your most challenging needs. A highly skilled team of medical professionals including physicians, scientists, medical technologists, medical technicians, lab assistants, biologists, chemists, microbiologists, geneticists, and other specialists work collaboratively. The department receives specimens for testing from patients and collection centers and is a reference laboratory for other clinics and hospitals both nationally and internationally. Lifecare's mission is to support the local delivery of laboratory services through the provision of exceptional reference laboratory services and by providing support services that facilitate and augment community integration efforts. We ensure Quality control programs that exceed industry guidelines for every patient sample. Proactive internal quality control team consisting of pathologists and laboratory personnel ensuring consistency and accuracy of specimen processing and diagnosis Our staff recognizes that specimens are patients, not just accession numbers in our lab. They are dedicated to combining the newest technologies, expertise, and quality in every sample they process.

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