Free Thyroxine

chart-icon

Take advantage of our packages

The Free Thyroxine is included in test packages, which you can buy at a lower price.

Free T4 is the metabolically active fraction of thyroxine and is the precursor of triiodothyronine (T3). Free T4 is a sensitive test for thyroid function and is increased with hyperthyroidism and decreased with hypothyroidism. Free T4 is not affected by changes in thryoxine-binding proteins. Information from Laboratory Test Handbook, Jacobs DS, DeMott WR, and Oxley DK, LexiComp, 2001.

More arrow
clock-icon

Awaiting result:

One day

syringe-icon

Collect material:

Blood

sun-icon

Prepare:

Learn more
Purpose of the test

The Thyroxine (T4) Test is a blood test designed to diagnose thyroid conditions. The thyroid, a small gland located at the base of the throat, produces hormones that regulate various bodily functions, including metabolism, temperature, and mood. The T4 test specifically measures the level of thyroxine, a type of thyroid hormone, in the blood. Abnormal levels of T4 can indicate thyroid disease.

Who Should Get Tested

Individuals suspected of having a thyroid problem may require a T4 test. Typically, a TSH test is conducted first, and if the results are abnormal, a T4 test follows. Symptoms of thyroid imbalances, such as weight gain, fatigue, sensitivity to temperatures, and irregular menstrual periods, can also prompt this test.

Blood Test Preparation Guidelines
Time of day
icon
It is recommended to schedule your appointment for blood tests in the morning hours between 7:00-10:00.
Fasting
icon
It is recommended to fast for approximately 12 hours before blood sampling. The last meal of the previous day should ideally be consumed around 6:00 p.m. On the day before the test, avoid heavy and fatty meals as well as alcohol.
Stay hydrated
icon
Drinking water prior to testing can help with sample collection.
Other factors
icon
Tests should not be performed after a sleepless night or intense physical activity. It is recommended to avoid exercise and stress immediately before blood collection and to not smoke. A short rest is recommended.
Medications and supplements:
icon
Blood samples should be collected before the morning dose. Some drugs can interfere with test results. Consult with your doctor whether you can delay your dose because of lab tests.
Biotin supplements:
icon
High doses of biotin supplements can affect test results, causing false elevation or reduction. It's recommended to avoid taking biotin for at least 72 hours before blood collection. If you are taking biotin, inform the personnel collecting the blood so that they can provide specific instructions.
Interpreting Test Results

T4 test results can be reported as "free T4" or "free T4 index (FTI)." Lower than normal T4 levels might indicate conditions like hypothyroidism or thyroiditis, while higher levels can suggest hyperthyroidism, thyroiditis, or other conditions. It's crucial to consult with a healthcare provider to interpret the results in the context of individual health and symptoms.

AI-Powered Insights and Expert Validation
Advanced AI Interpretation
Diagu's AI system represents a breakthrough in medical test analysis, employing state-of-the-art algorithms meticulously trained on a vast spectrum of authoritative medical literature and data. This system intricately analyses laboratory test results, extracting nuanced insights that might elude conventional methods. Our AI delves into complex interrelations between various health markers, offering a comprehensive understanding that supports accurate diagnosis and effective treatment planning. The foundation of our AI's analytical prowess lies in its extensive training, encompassing data from globally recognised medical journals, trusted healthcare databases, and breakthrough scientific studies. This ensures that every analysis is grounded in the latest and most comprehensive medical knowledge.
Expert Doctor Confirmation
While our AI provides deep analytical insights, the human touch remains indispensable. Every AI-generated interpretation is meticulously reviewed by experienced medical professionals, ensuring a harmonious blend of advanced technology and expert clinical judgment. This dual-layer approach guarantees that the insights provided are not only technologically sophisticated but also clinically relevant. Our medical experts ensure that the AI's interpretations align with current medical standards and practices, adding a layer of validation that only seasoned healthcare professionals can provide. This process reinforces the reliability of the test results, offering peace of mind to both patients and healthcare providers.
Language Model and Trusted Sources
At the core of Diagu's AI system is an advanced language model, engineered to transform complex medical data into clear, comprehensible, and informative descriptions. This model is adept at articulating detailed test analyses in a way that is accessible to both healthcare professionals and patients. The model's development involved the meticulous processing of high-quality sources, including reputable medical websites, renowned medical textbooks, and peer-reviewed research papers. This ensures that the language used in test descriptions is not only accurate and informative but also up-to-date with the latest medical findings and trends. By leveraging this rich tapestry of trusted sources, our AI system provides a deeper understanding of each test, fostering informed decision-making and enhanced patient care.