Total T3 (Triiodothyronine, Total)

CPT: 84480
Thyroid

What This Test Measures

Measures total T3 (bound + free); used in evaluation of hyperthyroidism and T3 toxicosis.

Preparation

No fasting required
If taking T3 medication (liothyronine/Cytomel), draw at least 12–24 hours after your last dose for an accurate TSH. If splitting T3 doses, draw at your natural trough. Biotin supplements — even in multivitamins — can falsely skew thyroid results: discontinue at least 2 days before testing. No fasting required unless combined with other tests.

General guidelines only. Requirements vary by lab and individual. Confirm with your provider before adjusting any medications.

Turnaround Time

Varies by lab

Clinical Notes

Less common; Free T3 generally preferred

ICD-10 Codes

Common diagnosis codes associated with this test. Codes are assigned by your provider.

E03.9Hypothyroidism, unspecified
E05.90Hyperthyroidism, unspecified
R53.83Other fatigue

Self-Pay Pricing

Coming Soon

Price comparison across labs will be available soon. Here are the labs we'll cover:

LabLooker may earn a commission through lab links. This does not affect pricing or rankings.

Quest Diagnostics--
LabCorp--
Ulta Lab Tests--
Walk-In Lab--
Any Lab Test Now--
Request A Test--
HealthLabs.com--
Private MD Labs--
DirectLabs--
Personalabs--
Life Extension--

Lab Codes

Proprietary codes used by each lab for this test.

ARUP Laboratories
0070143(order_code)
LabCorp
002188(order_code)
Quest Diagnostics
859(order_code)

Generate Doctor Request Template

Get a pre-filled template with test name, CPT code, and ICD-10 codes to bring to your appointment.

Upgrade to Premium

Related Tests

Free T4 (Thyroxine, Free)

CPT: 84439

Free T3 (Triiodothyronine, Free)

CPT: 84481

Free T4 Index (T7)

CPT: 84479, 84436

Anti-TPO (Thyroid Peroxidase Antibody)

CPT: 86376

Anti-Thyroglobulin Antibody (TgAb)

CPT: 86800

Comprehensive Thyroid Panel

CPT: 84443, 84439, 84481, 84482, 86376, 86800

For informational purposes only

This page is for educational and research purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. ICD-10 and CPT codes are assigned by your healthcare provider. Always consult a qualified healthcare provider before ordering any lab test or making decisions about your health.