**Note: All laboratory testing requires an authorizing physician. DHA Laboratory offers a patient direct program that partners you with an authorizing physician. If you have any additional questions regarding the availability of testing, please contact our laboratory by telephone or email.**
T3, Free is used in the evaluation of thyroid function. T3 is a hormone produced by the thyroid gland and helps control the rate at which your body generates energy.
Patient Preparation: Discontinue any supplements containing Biotin for 72 hours prior to specimen collection.