T4, Total, Plasma or Serum

Test Code

CPT Codes

Preferred Specimen
Submit only 1 of the following specimens:


Draw blood in a green-top (heparin) tube or a lavender-top
(EDTA) tube. Spin specimen down and send 0.5 mL
of plasma.

Note: 1. Indicate plasma.

2. Label specimen appropriately (plasma).


Draw blood in a plain, red-top tube or a serum gel tube. Spin
specimen down and send 0.5 mL of serum.

Note: 1. Indicate serum on request form.

2. Label specimen appropriately (serum).

Transport Temperature
Refrigerate up to 5 days hours/Frozen OK 

Competitive Immunoassay

Setup Schedule
Monday through Sunday

Reference Range

4.5-12.0 µg/dL

Performed By
North Mississippi Medical Center Pathology Department

Performing Laboratory
NMMC Pathology Department

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.