Find out what additional tests Dr. Friedman performs to evaluate the TSH levels by listening on the EmpowHer podcast.
Diagnosing all types of hypothyroidism is important, because treatment with thyroid hormone will improve symptoms in patients with hypothyroidism, but is unlikely to help those who do not have hypothyroidism. In primary hypothyroidism, the thyroid gland, located in the neck, is less able to produce the thyroid hormones, T4 and T3. The pituitary gland, located in the head, responds to this deficiency by secreting more TSH. Thus, in more mild cases of primary hypothyroidism, T4 and T3 levels are normal, but the TSH is high. In more severe cases, T4 and T3 levels drop. Although the normal range for TSH is often between 0.5 and 5 mU/mL, values at
the high end of the normal range may be abnormal. T3 is the more bioactive hormone compared to T4, but T4 is more stable in the circulation.
My approach to diagnosing hypothyroidism is to start with a careful history and physical.