Triiodothyronine Free
FT3
Description
Triiodothyronine Free (FT3) test measures the level of unbound triiodothyronine in your blood, helping doctors assess your thyroid function and metabolism. It’s often used to diagnose and monitor thyroid conditions like hyperthyroidism or hypothyroidism. A blood sample is taken to determine whether FT3 levels are too high or too low, which could indicate an imbalance in thyroid hormones. This test is especially useful if you’ve been dealing with symptoms like fatigue, weight changes, or an irregular heartbeat. The results help your doctor figure out what’s going on and decide on the best treatment, whether that’s medication, lifestyle changes, or more tests. Checking FT3 levels regularly helps keep your thyroid health and metabolism in balance.
Procedure
Invasive
Sample Type
Blood – Serum
Test Category
Hormones
Procedure Category
Blood Draw
Units
Picograms Per Milliliter
Test Groups
Basic Thyroid Group: This group includes essential tests for evaluating thyroid function and detecting common thyroid disorders. Complete Thyroid Group: A comprehensive array of tests for a thorough evaluation of thyroid function, providing detailed insights into thyroid health and associated conditions. Female Health Group: A comprehensive array of tests provides insights into various aspects of female health and wellness, aiding in the evaluation and management of overall health for females. Male Health Group: A comprehensive array of tests provides insights into various aspects of male health and wellness, aiding in the evaluation and management of overall health for men.
Optimal Range
For All Individuals:
Conventional Unit: 3.8–4.4 pg/mL
SI Unit: Not Applicable
Normal Range
For All Individuals:
Conventional Unit: 2.0–4.4 pg/mL
SI Unit: Not Applicable
Results That Differ From The Norm (Direct and Indirect Causes)
Increased levels may indicate:
Acute psychiatric illness
Cirrhosis (Scarring of the liver)
Graves' disease (Autoimmune disorder causing hyperthyroidism)
Hepatitis (Inflammation of the liver)
Hyperthyroidism (Overactive thyroid function)
Medications (such as contraceptives or estrogens)
P...
Key Reasons For Testing
Thyroid Function Assessment: Measures FT3 levels to evaluate thyroid function and diagnose thyroid disorders.
Hyperthyroidism Diagnosis: Detects elevated FT3 levels, aiding in diagnosis and monitoring.
Hypothyroidism Monitoring: Tracks FT3 levels during thyroid hormone replacement therapy for optimal efficacy.
Thyroid Hormone Conversion Evaluation: Evaluates T4 to T3 conversion, detecting abnormalities in ...
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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