What is a thyroid panel?
Last updated September 3, 2026.
A thyroid panel checks the gland that sets your metabolic speed. TSH is the screening test - the brain's thermostat signal, read inversely: an underactive thyroid drives TSH up, an overactive one drives it down. T4 confirms and grades, T3 joins for overactive questions, per MedlinePlus. Why it gets ordered: the symptoms of a mistuned thyroid are famously vague - underactive: fatigue, weight gain, cold intolerance, constipation, low mood; overactive: racing heart, weight loss, jitters, heat intolerance - so the blood test ends the guessing. Context matters: pregnancy, recent illness, and even biotin supplements can shift numbers, and a mildly abnormal TSH often earns a repeat in weeks before treatment. Pymander is a free AI doctor, 24/7 by text, and can help you read your result.
What to do
- TSH is the front door: other tests follow only if it flags.
- Mention everything you take: biotin and some medications skew assays.
- Mildly off? Expect a repeat: confirmation before treatment is normal.
- Symptoms plus a real abnormal number = the answer: either alone is not.
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