Question: What are the proper tests for thyroid dysfunction? My hair is falling out and I am very fatigued.
Dr Hibberd's answer:
Thyroid function is usually screened for by the use of an ultrasensitive TSH blood test — short for thyroid stimulating hormone. TSH causes the thyroid to make two hormones, triiodothyronine (T3) and thyroxine (T4), that regulate metabolism. In certain circumstances, free levels of T4 and T3 may be advised, especially when an overactive thyroid is suspected.
Hair loss and fatigue, while more commonly associated with an underactive thyroid (hypothyroidism), is also seen with overactive thyroid conditions (hyperthyroidism), as well as with a wide variety of other medical conditions.
These tests are inexpensive, and can be done with a simple blood sample. Results are usually available within an hour.
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