Purpose of the test

The thyroid panel is used to see how well the thyroid gland is functioning. This gland is responsible for producing hormones important for many bodily processes. Abnormal thyroid function, such as underactive thyroid (hypothyroidism) or overactive thyroid (hyperthyroidism), can lead to many symptoms. By measuring levels of thyroid hormones in the blood, the panel can help diagnose thyroid disorders and disrupted thyroid function.

A thyroid panel can also be used to monitor the treatment of hyperthyroidism and assess those receiving levothyroxine therapy, which replaces or supplements thyroid hormones reduced or absent due to hypothyroidism, thyroid cancer, thyroid nodules, and goiters.

What does the test measure?

The thyroid panel uses one blood sample to test for multiple elements related to thyroid function. Specifically, it measures the amounts of thyroid hormones and thyroid-stimulating hormones in the body.

Three hormones are part of a standard thyroid panel:

• Thyroid-stimulating Hormone (TSH)
• Free T4 (thyroxine)

When should I get this test?

Consider getting a thyroid panel if you feel symptoms of hyperthyroidism or hypothyroidism. The tricky thing is the symptoms are varied and can be easily overlooked.

Common signs of an overactive thyroid:

• Nervousness, anxiety, and irritability
• Mood swings
• Difficulty sleeping
• Tiredness
• Heat sensitivity
• Diarrhea
• Frequent urination
• Persistent thirst
• Itchiness
• Loss of interest in sex

Symptoms of an underactive thyroid include:

• Tiredness
• Sensitivity to cold
• Weight gain
• Constipation
• Depression
• Slow movements and thoughts
• Muscle aches and weakness
• Muscle cramps

Another reason to get a thyroid test is if you are currently undergoing thyroid treatment and your doctor wants to determine whether it is effective or if your thyroid feels enlarged.