Suspecting Thyroid Dysfunction

Symptoms of thyroid dysfunction include weight gain or loss, heat or cold intolerance, palpitations, hair loss, fragile nails, easy fatigue, menstrual, bowel irregularities and mood disturbances. These symptoms are not specific to the thyroid and may be due to other causes.

Blood tests for thyroid function may be useful for diagnosing thyroid disorders. These include Thyroid Stimulating Hormone (TSH), free T4 and free T3. TSH is produced by the pituitary gland and helps the thyroid gland develop during infancy into adulthood and to produce thyroid hormones T4 and T3.


Hyperthyroidism (overactive thyroid) is likely, when free T4 and/or free T3 levels are high and TSH is low. Causes include Grave’s disease, toxic thyroid nodule, viral thyroiditis or medication-induced. A nuclear medicine scan may help to differentiate between Grave’s disease and thyroiditis. Thyroid ultrasound may show thyroid nodules or increased blood flow, suggesting thyroid inflammation.