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Free T4

About This Test

Department: Biochemistry


  • Gel/clotted (yellow/red top)

Add-on requests are accepted up to 48 hours post sampling


Turnaround Time:

Within 24 hours


Investigation of thyroid dysfunction

Please indicate if patient is currently being treated for thyroid dysfunction (e.g. thyroxine/carbimazole/thyroidectomy) in order to aid interpretation.

Samples will not be analysed if previous analysis performed within 6 weeks. If there is a specific clinical reason for analysis within this timeframe, please state this on the request card

Reference ranges:

Age range Reference range (pmol/L)
All ages/sexes 12 - 23

Results outside the reference range do not necessarily indicate disease. Similarly, results within the reference range do not preclude abnormality. Please contact the Duty Biochemist for discussion of individual patient results.

Other Comments:

For more information, please see the following: Free T4 - Lab Tests Online

See also: TSHfree T3