£115.00
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Results: ~3 working days
Doctor’s report included
Convenient home or clinic sampling
Free delivery & returns
The thyroid function test measures thyroid-stimulating hormone (TSH) produced by the pituitary gland to regulate thyroid activity, free thyroxine (free T4 or FT4) as the main hormone produced by the thyroid gland, and free tri-iodothyronine (free T3 or FT3) as the active form converted from T4. These help assess thyroid function and detect imbalances.
Sample collection: A small blood sample is taken (usually serum tube) by a finger-prick kit at home or in one of our UK clinics. Our kit includes everything needed; simply return the sample in the pre-paid envelope. Results include a personalised doctor’s interpretation.
Age restriction: Adults 18+ only (guardian consent required for minors).
Thyroid function tests (TFTs) are common blood tests that evaluate the hormones produced by the thyroid gland. They check for disorders like hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid), which can affect metabolism, energy levels, and overall health. Your doctor may order TFTs as part of a routine check-up or if you have symptoms such as fatigue, weight changes, or mood issues. The test helps catch problems early by showing abnormal hormone levels. Swift Blood Tests processes samples rapidly, with results and a doctor’s report typically within a few days.
produced by the pituitary gland to stimulate the thyroid; high levels may indicate hypothyroidism, low levels hyperthyroidism.
the unbound form of thyroxine, the primary thyroid hormone; low levels suggest hypothyroidism, high levels hyperthyroidism.
the active unbound form of tri-iodothyronine, converted from T4; often measured in suspected hyperthyroidism or to assess severity.
A venous blood sample is required (collected in a gold top gel tube). No special patient preparation (such as fasting) is needed for standard TFTs, though inform us of medications like biotin supplements. Simply drink water and eat normally unless otherwise instructed. Send samples via the next-day laboratory service.
High TSH with low FT4/FT3 suggests underactive thyroid.
Low TSH with high FT4/FT3 indicates overactive thyroid.
Used to check thyroid hormone replacement or anti-thyroid drugs.
Abnormal patterns may flag hypothalamic-pituitary disorders. The test provides an overall snapshot of thyroid health and often leads to more specific follow-up tests if abnormalities are found.
You may be advised to take a thyroid function test if you have any of the following signs or risk factors: - Symptoms of hypothyroidism: fatigue, weight gain, feeling cold, constipation, dry skin. - Symptoms of hyperthyroidism: weight loss, rapid heartbeat, anxiety, heat intolerance. - Family history of thyroid disorders or autoimmune conditions. - Chronic conditions: monitoring for those on medications like lithium or amiodarone that affect thyroid function. For example, a patient feeling unusually tired may have high TSH indicating hypothyroidism. Your doctor will interpret the results alongside your history and may order additional tests based on the findings.
If you can’t find the test you’re looking for, simply give us a call and our support team will guide you to the right option. We’re here to ensure you get the correct test quickly and confidently.
A thyroid function test measures TSH, free T4, and free T3 to assess thyroid gland activity and hormone production. It provides a broad overview of your thyroid health.
It is often ordered for symptoms like fatigue, weight changes, or irregular heart rate, or to monitor thyroid disorders.
No special preparation is usually required. You can eat and drink normally, but mention any medications.
A small blood sample is taken from a vein in your arm using a needle. It is quick (often under 5 minutes) and routine. You may feel a brief pinch; afterwards, a bandage is applied. There are minimal risks.
Risks are very low. You might experience slight pain or bruising at the needle site, which usually resolves quickly.
Results are typically available within 2–3 working days. Swift Blood Tests provides a detailed doctor’s report explaining your results. You will be notified by email or phone as agreed.
Yes. Swift Blood Tests offers a convenient home sample collection kit (finger-prick or small tube) with instructions, or you can choose a clinic appointment. Follow the included instructions to collect and return the sample by post.
Medications like amiodarone, lithium, or biotin, recent illness, or pregnancy can influence levels. It’s best to mention any current health conditions or medicines when you discuss results with the doctor.
An abnormal result does not always mean disease. For example, high TSH might indicate hypothyroidism, while low TSH could suggest hyperthyroidism. Your doctor will interpret any out-of-range values and may recommend follow-up tests.
This test is intended for adults (18+). Children’s normal thyroid values differ from adults. If testing is needed for a child or teenager, please consult with a paediatric specialist or contact us for guidance.
