Frequently bought with this test
Thyroid Function (TSH & Free T4)
If you’ve been feeling unusually tired, gaining or losing weight unexpectedly, experiencing changes in mood, hair loss, or struggling with temperature regulation, your thyroid could be playing a role. Our Thyroid Function Blood Test measures two key markers — TSH (thyroid stimulating hormone) and Free T4 (thyroxine) — to give a clear picture of how well your thyroid is working.
4/5
£49
Frequently bought with this test
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Essential information about your test
Understanding Thyroid Function
This test measures two hormones — TSH and Free T4 — to assess how well your thyroid is working. The thyroid gland plays a major role in regulating metabolism, energy, and mood. Imbalances can cause symptoms ranging from fatigue and weight changes to anxiety and palpitations.
What we measure:
Produced by the pituitary gland, TSH regulates how much hormone your thyroid makes. High TSH often indicates an underactive thyroid (hypothyroidism), while low TSH may suggest an overactive thyroid (hyperthyroidism).
- Key marker for thyroid balance
- High = underactive thyroid
- Low = overactive thyroid
The main hormone released by the thyroid gland. It controls your body’s metabolism — how you convert food into energy. Measuring Free T4 alongside TSH helps confirm thyroid function or imbalance.
- Primary thyroid hormone
- Direct measure of metabolism
- Used to confirm overactive/underactive thyroid