Hormones . Symptoms guide
Thyroid Symptoms: When and What to Test
Thyroid disease is common, often subtle, and easy to miss on a TSH-only test. Full thyroid screening covers TSH, free T3 and free T4 in one draw, with the option to add thyroid antibodies if autoimmune disease is suspected. Our Advanced Hair and Hormone Check and Hormone Specialist panels both include a full thyroid screen.
This patient information is being clinically reviewed by our team. The factual content draws on UK guidance (NHS, NICE, British Association of Dermatologists, British Society for Sexual Medicine where cited).
What this might be
- Hypothyroidism. Tiredness, weight gain, cold intolerance, hair loss, low mood.
- Hyperthyroidism. Anxiety, weight loss, palpitations, heat intolerance.
- Subclinical thyroid disease. TSH outside range, T3 and T4 normal. Often best detected with the full panel.
- Hashimoto thyroiditis. Autoimmune; antibodies on request.
Common features that suggest this
- Persistent fatigue not explained by sleep
- Unexplained weight change
- Hair thinning or shedding
- Cold or heat intolerance
- Anxiety, palpitations, or tremor
- Constipation or loose stools
Recommended tests
Same-day appointments at our Harley Street clinic, results clinician-reviewed.
Need a marker not in these panels? Build a custom panel and a GMC-registered clinician will design one for you.
Testing advice
No fasting required. Morning sample is preferable. If you take levothyroxine, take it after the blood draw rather than before.
Common questions
Why test free T3 and T4 if my TSH is normal?
TSH-only testing misses up to 5 percent of thyroid dysfunction. Free T3 in particular reflects active hormone levels and is useful when symptoms are present but TSH is borderline.
Can you add thyroid antibodies?
Yes, on clinician request. Useful for confirming Hashimoto or Graves disease.
Related symptoms
Sources and further reading
This page provides general information only and is not a substitute for medical advice. A GMC-registered clinician will review your results and tailor any recommendations to you personally.