Description

The TSH Reflex to Free T4 test evaluates your thyroid function by first measuring your level of thyroid-stimulating hormone (TSH). TSH is produced by the pituitary gland and helps regulate how much thyroid hormone your body makes.

If your TSH level is found to be too high or too low, the lab will automatically perform a Free T4 (Free Thyroxine) test on the same sample. Free T4 is the active form of thyroid hormone and gives a clearer picture of how well your thyroid is functioning.

This test helps identify thyroid conditions such as:

  • Hypothyroidism (underactive thyroid)
  • Hyperthyroidism (overactive thyroid)
  • Thyroid hormone imbalances due to medication or other health conditions

Common symptoms of thyroid dysfunction include:

  • Fatigue or low energy
  • Weight changes
  • Sensitivity to cold or heat
  • Hair thinning or dry skin
  • Mood changes like depression or anxiety

Knowing both your TSH and Free T4 levels can guide your healthcare provider in diagnosing and managing thyroid conditions accurately and efficiently.

Fasting: Not required.