Thyroid Function Test （In store/ Home）

The Thyroid Function Test is a 2-marker blood test measuring TSH and free T4 to check whether your thyroid is working normally, processed by London Medical Laboratory (LML), a UKAS-accredited ISO 15189 laboratory, and sold by Ways Pharmacy (UK).

Key facts

Who it is for

• People with symptoms that can point to thyroid problems — fatigue, weight change, low mood, feeling too hot or too cold
• People who want a basic check of thyroid function without the wider antibody panel
• People on thyroid medication who want to monitor TSH and free T4 between GP reviews
• People with a family history of thyroid disease wanting a screening check

Not suitable for: people who want autoantibody testing (consider the Total Thyroid Profile, which adds TPO and antithyroglobulin antibodies and free T3); acutely unwell people who need urgent assessment; replacement for assessment by a doctor.

What is measured

• Thyroid Stimulating Hormone (TSH) — the pituitary hormone that signals the thyroid; the most sensitive first-line marker of thyroid function
• Free T4 (thyroxine) — the main thyroid hormone in its unbound, active form, interpreted alongside TSH

Abnormal thyroid hormones can contribute to fatigue, mood changes and weight problems. Results are interpreted alongside your symptoms.

How it works

1. Complete payment online and choose your option: an appointment at Holborn London, or an at-home self-collection kit posted to you.
2. For in-store, attend Ways Pharmacy, 77 Southampton Row, London WC1B 4ET, where a trained operator takes one tube of venous blood. For at-home, follow the kit instructions to collect a finger-prick sample and return it in the prepaid packaging.
3. Your sample is sent to London Medical Laboratory for analysis.
4. You receive a written report with each marker against its reference range, typically within 3–5 working days.
5. A pharmacist can talk you through the result and, where appropriate, recommend GP follow-up.

Frequently asked questions

Do I need to fast before a thyroid test?

No. A thyroid function test does not require fasting, so you can eat and drink as normal. If you take thyroid medication, ask the pharmacist about timing, as it can affect the reading; otherwise take your usual medicines unless your GP has advised otherwise.

How long do results take?

Results are typically returned 3 to 5 working days after London Medical Laboratory receives your sample. You will receive a written report showing each marker against its reference range.

Is the laboratory accredited?

Yes. Samples are processed by London Medical Laboratory (LML), a UKAS-accredited laboratory operating to ISO 15189, the international standard for medical testing laboratories.

What is the difference between this and the Total Thyroid Profile?

This test measures TSH and free T4 — a basic check of thyroid function. The Total Thyroid Profile adds free T3 and two thyroid antibodies (TPO and antithyroglobulin), which help investigate autoimmune thyroid conditions. Ask the pharmacist if you are unsure which is right for you.

What if my result is abnormal?

An out-of-range result does not diagnose a condition on its own. The pharmacist will explain what it means and recommend GP follow-up where appropriate, which may include repeat testing. Reference ranges are provided with your report.

When to seek further advice

This test does not diagnose a thyroid condition. Reference ranges are provided with your report; discuss your results with a clinician, and if a result is abnormal, follow it up with your GP. Seek prompt medical advice if you feel acutely unwell.

This is a private health screening service. Results are interpretive and do not replace clinical diagnosis by a GP or specialist. Abnormal results should be followed up with your GP.