The thyroid produces hormones that regulate the body's metabolic rate-controlling heart, muscle and digestive function, brain development and bone maintenance. Problems with the thyroid can cause various medical issues and can lead to either hyperthyroidism or hypothyroidism.
Thyroid function tests look at levels of thyroid-stimulating hormone (TSH) and thyroxine (T4) in the blood. You may also hear medical practitioners refer to this as “free” T4 (FT4). A high level of TSH and a low level of T4 in the blood could mean you have an underactive thyroid or vice versa.
The usual blood tests carried out for thyroid function are TSH, T4 and occasionally T3, but generally TSH level will be the first hormone to be measured, as if this is normal, it is most likely that your thyroid is functioning normally. Where there is a concern of a pituitary problem, T4 should be measured as well.
Doctors will interpret thyroid function test results, together with your symptoms and how you’re feeling, in order to determine whether thyroid disease is suspected, the severity of it and how to treat it.
Often a ‘cascade’ system is employed by doctors, so other hormones are measured if TSH is not normal.
If the TSH level is above the reference range, T4 will be measured. And if it is below the reference range, both T4 and T3 will be measured.
A blood sample is taken from a vein in the arm and sent off to our laboratory, The Doctors Laboratory, for analysis. In addition, Bodyvie offers a comprehensive range of most blood testing via its testing lab – The Doctors Laboratory.
To enquire about other tests please simply contact us via our contact form or give us a call.
