TBG Thyroxine Binding Globulin Test
Short Name: TBG Test
Also known as: TBG Test, Thyroxine-Binding Globulin Test
TBG Thyroxine Binding Globulin Test test available at DNA Labs India for ₹13,000. Uses Immunoassay on Serum samples. Results in Samples received by the 7th of the month are processed and reports are issued in 2-3 weeks. You will receive the report via email, WhatsApp, or online portal.. Free home collection in 300+ cities across India.
🩺 Medically Reviewed By
Dr Ramarao Paidisetty
Consultant Biochemist · Reg: 21504
Last reviewed: September 7, 2026
Overview
The purpose of the TBG Thyroxine Binding Globulin test is to establish the presence of TBG deficiency or excess, which may be suggested by abnormal total serum T4 and T3 concentrations in the presence of normal free levels of these hormones. Definitive documentation of a TBG derangement can avoid unnecessary diagnostic procedures and therapy in individuals with harmless congenital TBG anomalies, as well as in their relatives.
- Test Code
- 3679
- CPT Code
- 84442
- ICD Code
- R94.6
- Price
- ₹13,000
- Sample Type
- Serum
- Result Time
- Samples received by the 7th of the month are processed and reports are issued in 2-3 weeks. You will receive the report via email, WhatsApp, or online portal.
- Fasting Required
- No
- Method
- Immunoassay
Sample Collection
No special preparation or fasting is required. Take your prescribed medications as usual. Complete the mandatory Test Send Out Consent Form (Form 35) before giving the blood sample.
Method: Venipuncture
Laboratory Analysis
A trained phlebotomist will collect blood from a vein in your arm using a sterile needle. The procedure takes about 5 minutes.
Report Delivery
Once the sample is collected, you can resume regular activities. Apply pressure to the venipuncture site for 1-2 minutes to prevent bruising.
Timeline: Samples received by the 7th of the month are processed and reports are issued in 2-3 weeks. You will receive the report via email, WhatsApp, or online portal.
Patient Instructions
About This Test
Who Should Get This Test
The purpose of the TBG Thyroxine Binding Globulin test is to establish the presence of TBG deficiency or excess, which may be suggested by abnormal total serum T4 and T3 concentrations in the presence of normal free levels of these hormones. Definitive documentation of a TBG derangement can avoid unnecessary diagnostic procedures and therapy in individuals with harmless congenital TBG anomalies, as well as in their relatives.
How to Prepare
- Fasting is not required
- Duly filled Test Send Out Consent Form (Form 35) is mandatory
- Samples are sent in batches by the 7th of the month
- Inform your doctor about medications such as estrogen or oral contraceptives
Doctor's Notes
Reviewed by Dr Ramarao Paidisetty — MBBS, MD (Biochemistry) · Reg. No. 21504
"When total T3/T4 are abnormal but free T3/T4 and TSH are normal, a TBG measurement is key in differentiating harmless binding-protein abnormalities from true thyroid disease."
Last medically reviewed: September 7, 2026
Test Parameters & Specifications
Sample Stability
- Insufficient sample volume (less than 1 mL)
- Improperly labeled serum sample
- Severely hemolyzed, lipemic, or icteric sample after centrifugation
- Missing signed Test Send Out Consent Form (Form 35)
Understanding Your Results
TBG excess, often from estrogen excess, pregnancy, or inherited cause.
TBG deficiency, often from androgen excess, catabolic states, or inherited cause.
Evaluate for primary thyroid dysfunction rather than binding protein abnormality.
Consult an endocrinologist if TBG levels are outside the reference range, if total and free thyroid hormones are discordant, or if you have symptoms of hypothyroidism or hyperthyroidism.
Limitations
- ⚠TBG measurement does not reflect free hormone levels
- ⚠Reference ranges may vary by age, sex, and laboratory
- ⚠Not useful for monitoring thyroid therapy alone
- ⚠Inherited TBG abnormalities are generally benign but require correct classification
Risks & Considerations
- ●Slight pain or throbbing at the needle site
- ●Small bruise (hematoma) at the venipuncture site
- ●Rare risk of infection or excessive bleeding
Interfering Factors
- ●Estrogen-containing medications and pregnancy can raise TBG
- ●Androgens, glucocorticoids, and severe systemic illness can lower TBG
- ●Heparin therapy can alter TBG binding
- ●Results should be interpreted with free T4, free T3, and TSH
Frequently Asked Questions
What is the TBG Thyroxine Binding Globulin test?
How much does the TBG Thyroxine Binding Globulin test cost in India?
Is fasting required before the TBG test?
What sample is collected for the TBG test?
What are the symptoms of thyroid disorders that may prompt this test?
How long does it take to get the TBG test report?
Is the TBG test covered by insurance?
Why is the Test Send Out Consent Form (Form 35) mandatory?
What does a high TBG level mean?
What does a low TBG level mean?
Can the TBG test alone diagnose hypothyroidism?
Is home sample collection available for the TBG test?
Related Tests
Reference Laboratory Services
We serve as a reference laboratory for hospitals and clinics across India. Send samples from your facility with same-day pickup, priority processing, and results delivered through our online portal. Competitive institutional pricing available.
Your Data Privacy
Your medical data is protected under Indian law.
✓ Stored in India: All patient records are stored on servers located in India. No data is transferred outside the country.
✓ DPDP Act Compliant: Under the Digital Personal Data Protection Act 2023, you can request deletion of your records at any time by contacting support.
Book Your Test
Enter your details and we'll connect you within 15 minutes.