thyroxine

Last reviewed 08/2022

Plasma thyroxine ranges between 70-150 nomol per litre and may be measured by radioimmunoassay. It is a very good screening test for primary hypothyroidism where it is lowered. It is elevated in hyperthyroidism.

Related pages:

thyroid hormone function

reference range (thyroxine)

clinical conditions requiring adjustment of thyroxine dose

T4, total, raised

T4, total, reduced

free T4

thyroid disease diagnostic algorithm

drugs affecting thyroxine (levothyroxine) dosage

pharmacokinetics of thyroid hormones (T3 and T4)