Reading your thyroid panel without panicking

A thyroid panel is one of the most commonly ordered blood tests in India — and one of the most commonly misread.

The three numbers

• TSH (Thyroid Stimulating Hormone) — produced by the pituitary. The most sensitive marker.
• Free T4 — the storage form of thyroid hormone.
• Free T3 — the active form.

What's normal

Marker	Typical range
TSH	0.4 – 4.5 mIU/L
Free T4	0.8 – 1.8 ng/dL
Free T3	2.3 – 4.2 pg/mL

Lab ranges vary slightly. Always read your own report's reference column, not Google's.

Common patterns

• High TSH + low T4 → primary hypothyroidism
• Low TSH + high T4/T3 → hyperthyroidism
• High TSH + normal T4 → subclinical hypothyroidism (often watched, not treated)
• All normal → fine, even if you feel tired (thyroid is rarely the answer to fatigue alone)

When "borderline" matters

Subclinical hypothyroidism (TSH between 4.5 and 10, normal T4) is the most over-treated finding in Indian outpatient medicine. It often resolves on its own. Repeat the test in 6–8 weeks before starting medication unless you're pregnant or planning to be.

Consistency matters more than precision

If you're tracking thyroid over time:

• Test at the same time of day (TSH varies through the day)
• Use the same lab where possible
• Don't take levothyroxine in the morning before the test — take it after

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Bring this report to your doctor, not to a forum. The numbers are simple; the interpretation needs context.