Quick answer
The Total T3 Test costs ₹250 at Live Line Health Care. Measures total triiodothyronine, mainly to look into a suspected overactive thyroid when TSH is low and T4 looks normal. No fasting is needed. It uses a blood sample and the report is usually ready the same day. Book home sample collection or visit any of our 45 centres.
Also known as: T3, Total Triiodothyronine, Triiodothyronine, Serum T3, S. T3, TT3, T3 Hormone
What is the Total T3 Test?
Total T3 measures triiodothyronine, the most active form of thyroid hormone, in your blood. The thyroid releases only a small share of it directly, and most T3 is made in the liver and other tissues by converting T4. "Total" means the test counts both the hormone carried on blood proteins and the tiny free portion that cells can use, so anything that changes those carrier proteins can shift the number.
On its own, this is a narrow test with one main job: looking for an overactive thyroid when TSH is low but T4 seems normal, a pattern known as T3 toxicosis, or following T3 during treatment. It is a poor first test, and it does not help to find an underactive thyroid, because T3 often stays normal until the condition is advanced. If you have not had a recent TSH, or this is your first thyroid check, book the full Thyroid Profile (T3, T4, TSH) instead.
What it measures: Total triiodothyronine (T3) in blood, including both protein-bound and free hormone, reported in ng/dL or ng/mL.
Parameters included (1)
- Total T3 (Triiodothyronine)
Why is this test done?
- Checking for an overactive thyroid when TSH is low and T4 is normal
- Detecting T3 toxicosis, which can occur with Graves’ disease or a toxic thyroid nodule
- Following T3 levels during treatment of hyperthyroidism
- Judging how severe an overactive thyroid is, alongside T4
- Monitoring people prescribed T3 (liothyronine) tablets, when a doctor requests it
When should you get tested?
- Your doctor has a recent low TSH report and has asked for T3 next
- Palpitations, tremors or heat intolerance with a T4 that came back normal
- Weight loss despite a good appetite, with a low TSH on record
- You are being treated for hyperthyroidism and your doctor wants to follow T3
- No recent TSH on record: the full Thyroid Profile is the better choice
How to prepare for the Total T3 Test
- 1No fasting is required.
- 2If you take thyroid medicine, ask your doctor whether to give the sample before that day’s dose. Liothyronine in particular raises T3 for some hours after a dose.
- 3Tell our staff if you take birth control pills, estrogen, steroids or amiodarone, or if you are pregnant, since these change total T3 or how it should be read.
- 4Bring your recent TSH report, since T3 is read alongside it. Biotin supplements can interfere with this test, so ask your doctor whether to pause them for 2 to 3 days.
Total T3 Test normal range
| Parameter | Typical reference range |
|---|---|
| Adults | 80–200 ng/dL (0.8–2.0 ng/mL) |
| Older adults | Often in the lower part of the adult range |
| Pregnancy | Can read up to about 1.5 times the non-pregnant range |
Some reports use nmol/L, where the typical adult range is about 1.2–3.1 nmol/L. Children have higher ranges that change with age. Ranges are typical adult values and vary between labs, age and sex. Always use the range printed on your report and discuss results with your doctor.
Understanding your results
- A high T3 with a low TSH supports an overactive thyroid. If T4 is normal, this is called T3 toxicosis, and your doctor will look for the cause, such as Graves’ disease or a nodule.
- A high total T3 with a normal TSH is often not a thyroid problem. Pregnancy, birth control pills and estrogen raise carrier proteins, and the hormone reading rises with them.
- A low T3 with a normal TSH is common during illness, fasting or after surgery, and it often returns to normal with recovery. It does not by itself mean an underactive thyroid.
- T3 can remain normal in an underactive thyroid until late, so a normal T3 does not rule that condition out.
Total T3 Test – FAQs
What is the price of the Total T3 Test?
The Total T3 Test costs ₹250 at Live Line Health Care, at all 45 centres and for home sample collection.
When is a Total T3 test enough instead of a Thyroid Profile?
It is enough when you already have a recent TSH and T4 and your doctor only wants T3 added, usually because TSH is low and T4 is normal. For a first check or new symptoms, the Thyroid Profile is better because it includes all three hormones together.
Can T3 be normal if I have hypothyroidism?
Yes. In an underactive thyroid, the body converts more T4 into T3 to compensate, so T3 often stays normal for a long time. That is why doctors use TSH and T4, rather than T3, to diagnose and follow hypothyroidism.
What is the difference between total T3 and free T3?
Total T3 counts hormone bound to blood proteins plus the small free fraction. Free T3 counts only the unbound part that cells can use. Total T3 is affected by pregnancy and birth control pills, which raise carrier proteins, while free T3 is a separate test.
What is T3 toxicosis?
T3 toxicosis is a form of overactive thyroid where T3 is high while T4 stays normal and TSH is low. It may appear early in Graves’ disease or with a toxic nodule. A T4 test alone would miss it, which is why doctors add T3.
Why is my T3 low when I have a fever or illness?
During illness, fasting or recovery from surgery, the body slows its conversion of T4 into T3. This often reverses on recovery and does not usually mean thyroid disease. Doctors generally recheck thyroid tests after you have recovered, unless there is a strong reason to act sooner.
Do birth control pills affect total T3?
Yes, they can. Estrogen raises the protein that carries thyroid hormone, so total T3 can read higher even when the thyroid is working normally. Mention the pill when you give the sample, and do not stop it on your own because of this result.
Where can I get the Total T3 Test done?
At any of our 45 Live Line Health Care centres in 40 cities across Andhra Pradesh and Telangana, including Hyderabad, Visakhapatnam, Warangal, Kakinada and Nellore, or book home sample collection.
Medical disclaimer: This information is for general awareness only and is not a substitute for professional medical advice. Please consult a qualified doctor to interpret your results and before starting or changing any treatment.