Thyroid Profile 3 measures TSH and the two active thyroid hormones, Free T3 and Free T4, to check whether your thyroid gland is under or overactive. It's typically requested for symptoms such as fatigue, weight change, palpitations or mood changes, or to monitor existing thyroid treatment. The test costs £142.50, plus a £50 blood-draw fee, with results back within 1 day. You can walk in or book online at 117a Harley Street, seven days a week, with no GP referral needed.
Doctors commonly order this panel for symptoms that could point either way, including persistent tiredness, unexplained weight change, feeling too hot or too cold, palpitations, hair thinning or changes in mood.
It is also used to monitor people already on thyroid medication such as levothyroxine, since the dose often needs adjusting over time, or to check thyroid function during other health investigations such as fertility or menopause assessments.
A family history of thyroid disease, or an existing autoimmune condition, are further common reasons a doctor requests a full thyroid check rather than TSH alone.
No special preparation is listed for this profile, and most people do not need to fast beforehand. Thyroid hormone levels are fairly stable through the day, though it's best to take the test at a similar time if you are comparing it with a previous result, and to follow any instruction from your doctor.
A raised TSH alongside a low Free T4 commonly suggests an underactive thyroid, while a low TSH alongside a raised Free T3 or Free T4 commonly suggests an overactive one. Results in between, or where TSH and the free hormones do not move together, need a clinician to interpret them alongside your symptoms.
Thyroid results can also be affected by pregnancy, certain medicines, and recent illness, so your laboratory report and its reference range are only one part of the picture. If your results fall outside range, or your symptoms continue despite a normal result, book a doctor's appointment to discuss next steps.
If you want these markers alongside a doctor's examination and a wider health assessment, compare the Full Body MOT health check.
Written by Mr Stephen Lingam. Reviewed by Dr Mohammad Bakhtiar.
TSH is the signal from the pituitary gland asking the thyroid to work harder or ease off, while Free T4 is one of the hormones the thyroid actually produces. Looking at both together gives a clearer picture than either alone.
T4 converts to the more active T3 hormone in the body, and measuring both can help when TSH and Free T4 results don't fully explain your symptoms.
Yes, recent illness, certain medicines and even significant stress can temporarily shift thyroid readings, which is one reason results are interpreted alongside your history rather than in isolation.
This varies by individual and is best set by your doctor, though many people on thyroid medication are checked periodically until their dose is stable, then less often after that.