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Rishabh Kumar

B.Pharm

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Dr. Swati Gupta (Anand)

MD Lab Medicine, MBBS

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Thyroid Profile Total (T3, T4 & TSH)

Also known as Thyroid Panel, TFT, Thyroid Function Test

Thyroid Profile Total (T3, T4 & TSH) Includes 3 testsView All

₹490~~₹550~~ 10% Off

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation is required.
Do not stop taking your thyroid medications on the day of the test unless otherwise advised by the doctor.

Understanding Thyroid Profile Total (T3, T4 & TSH)

What is Thyroid Profile Total (T3, T4 & TSH)?

The Thyroid Profile Total (T3, T4 & TSH) offers a series of blood tests that measure the levels of thyroid hormones in the blood. Together, these tests help identify how well your thyroid gland works. It includes tests for thyroid-stimulating hormone (TSH), thyroxine hormone (T4)- total, and triiodothyronine hormone (T3)- total.

The thyroid gland is a butterfly-shaped organ located in the neck. It produces hormones like thyroxine (T4) and triiodothyronine (T3). These hormones are responsible for regulating metabolism and other bodily functions. The production and release of T3 and T4 are controlled by the thyroid-stimulating hormone (TSH), which is produced by the pituitary gland.

Your doctor may advise this test if you show any symptoms suggestive of thyroid disorders (hyperthyroidism and hypothyroidism). Symptoms of hyperthyroidism include weight loss, nervousness, irritability, increased sweating, and rapid heartbeat. Symptoms of hypothyroidism such as weight gain, fatigue, sensitivity to cold, constipation, and dry skin. This test is also recommended for women during pregnancy to check if they have adequate amounts of thyroid hormones. These hormones are important for the healthy development of babies.

Total T3 & T4 levels are altered by physiological or pathological changes in thyroxine binding globulin (TBG) capacity. TBG is the transport protein that binds and transports thyroid hormones to the necessary tissues. TSH may show marked fluctuations in an individual due to a number of factors, one of which is the time of the day when it is measured. So, the daytime testing for TSH measurements is usually preferred.

No special preparations are needed for this profile. Usually, you do not need to stop taking your thyroid medication before taking this test. However, let your doctor know about all the medications you take, as some of them can affect thyroid function.

Lab test results may vary across laboratories. Interpretation of the test results requires expert guidance. Therefore, do not self-medicate and talk to your doctor to understand your test results correctly.

What is Thyroid Profile Total (T3, T4 & TSH) used for?

The Thyroid Profile Total (T3, T4 & TSH) is done:

As part of routine checkups to monitor your overall health.
To find out the cause of symptoms like tiredness, weight changes, hair loss, fast or slow heartbeat, dry skin, or feeling too cold.
To check for thyroid problems like hypothyroidism, hyperthyroidism, Graves’ disease, thyroiditis, or Hashimoto’s disease.
To check how well the treatment is working.
To detect an underactive thyroid gland in newborn babies.

What does Thyroid Profile Total (T3, T4 & TSH) measure?

Contains 3 tests

The Thyroid Profile Total (T3, T4 & TSH) measures the levels of three hormones in the blood. It includes triiodothyronine hormone (T3) total, thyroxine hormone (T4) total, and thyroid-stimulating hormone (TSH). T3 and T4 are thyroid hormones that help regulate metabolism and energy levels in the body. On the other hand, TSH is produced by the pituitary gland and stimulates the thyroid gland to produce T3 and T4 hormones. The levels of thyroid hormones (like T4) and TSH in the blood are linked in an opposite way. This means when T4 is low, like in hypothyroidism, TSH is usually high. When T4 is high, like in hyperthyroidism, TSH is usually low.

Triiodothyronine Total

The Triiodothyronine Total test measures triiodothyronine, also known as T3, hormone that is produced by the thyroid gland. T3 hormone plays an important role in regulating the body's metabolism, energy levels, and growth & development. It exists in the blood in two forms: free T3 and bound T3. Free T3 is not bound to proteins in the blood and is the active form of T3. Whereas, bound T3 is bound to proteins, such as albumin and thyroid hormone binding globulin (THBG), which prevent it from entering the body tissues.

Know more about Triiodothyronine Total

TSH (Thyroid Stimulating Hormone) Ultrasensitive

The TSH (Thyroid Stimulating Hormone) Ultrasensitive test measures the levels of TSH hormone in the blood. TSH is produced by the pituitary gland located in the brain. Its function is to stimulate and regulate the functioning of the thyroid gland. It signals the thyroid gland to increase or decrease the production of thyroid hormones T3 and T4 (essential for regulating our body’s metabolism, temperature, heart rate, and growth) when their levels are low or high, respectively. Therefore, when the levels of T3 & T4 decrease, the pituitary gland is stimulated to release TSH. This high TSH level, in turn, stimulates the thyroid gland to release more thyroid hormones (T3 & T4); the vice-versa happens when the levels of thyroid hormones increase.

Know more about TSH (Thyroid Stimulating Hormone) Ultrasensitive

Thyroxine - Total

The Thyroxine - Total test measures both the bound and unbound/free form of thyroxine (T4) hormone in the blood. T4 exists in the blood in two forms: bound (attached to proteins) and free (not attached to proteins). Most of the T4 circulating in the blood is bound to proteins and only a small part is free. It is necessary to maintain a fine balance of these forms to ensure the proper functioning of the body.

Know more about Thyroxine - Total

Interpreting Thyroid Profile Total (T3, T4 & TSH) results

Interpretations

T3 (Triiodothyronine), Total Reference Range(s)


	<1 Month	Not Established
	1-23 Months	117-239 ng/dL
	2-12 Years	105-207 ng/dL
	13-20 Years	86-192 ng/dL
	>20 Years	76-181 ng/dL

T4 (Thyroxine), Total

4.5-12.0 mcg/dL

Thyroid Stimulating Hormone (TSH) Reference Range(s)

Premature Infants (28-36 Weeks)
1st Week of Life	0.20-27.90 mIU/L
Term Infants (>37 Weeks)
Serum or Cord Blood	1.00-39.00 mIU/L
1-2 Days	3.20-34.60 mIU/L
3-4 Days	0.70-15.40 mIU/L
5 Days-4 Weeks	1.70-9.10 mIU/L
1-11 Months	0.80-8.20 mIU/L
1-19 Years	0.50-4.30 mIU/L
≥20 Years	0.40-4.50 mIU/L
Pregnancy
First Trimester	0.26-2.66 mIU/L
Second Trimester	0.55-2.73 mIU/L
Third Trimester	0.43-2.91 mIU/L

Table 1. Interpretation of the Thyroid Profile Test results

TSH	T4	T3	INTERPRETATION
Elevated	Normal	Normal	Mild (subclinical) hypothyroidism
Elevated	Low	Low or normal	Hypothyroidism
Low	Normal	Normal	Mild (subclinical) hyperthyroidism
Low	Elevated or normal	High or normal	Hyperthyroidism
Low	Low or normal	Low or normal	Nonthyroidal illness; hypothyroidism due to the disease involving the pituitary gland
Normal	Elevated	Elevated	Thyroid hormone resistance (Impaired sensitivity to thyroid hormone)

Low T4 and T3, along with high TSH level, indicates hypothyroidism. The most common cause of hypothyroidism is Hashimoto thyroiditis
High T4 and T3, along with low TSH, indicate hyperthyroidism. The most common cause of hyperthyroidism is Grave’s disease
Normal thyroxine (T4) and T3, along with high TSH, usually indicate mild or subclinical hypothyroidism
Normal T3 and T4, along with low TSH, indicate mild or subclinical hyperthyroidism

Note: TSH levels show circadian variation (fluctuates during the 24-hour cycle), reaching peak levels between 2 - 4 am and are at a low between 6-10 pm.

Reference Range(s) may vary from lab to lab.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Thyroid Profile Total (T3, T4 & TSH)

Frequently Asked Questions about Thyroid Profile Total (T3, T4 & TSH)

Q. Why is the Thyroid Profile Total (T3, T4 & TSH) performed?

The Thyroid Profile Total (T3, T4 & TSH) evaluates the functioning of the thyroid gland. It diagnoses disorders like hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid).

Q. Is fasting required for the Thyroid Profile Total (T3, T4 & TSH)?

No, fasting is not needed before taking this test. However, your doctor will guide you if any special preparation is required.

Q. Is there any risk associated with this test?

There is usually no risk associated with this test. Some people may feel a slight sting while the needle is pricked and may experience some bleeding, which is normal and usually not bothersome. Rarely, some people may experience slight swelling or bruising at the site of the needle prick. Applying ice 3-4 times a day for about a week may help reduce swelling and bruising. If it does not get better, consult your doctor.

Q. Can I take the Thyroid Profile Total (T3, T4 & TSH) during pregnancy?

Yes, the Thyroid Profile Total (T3, T4, and TSH) is often recommended during pregnancy. It checks thyroid hormone levels, as thyroid problems can cause complications during pregnancy.

Q. Can my Thyroid Profile Total (T3, T4 & TSH) test show variable results?

Yes, TSH levels in an individual may fluctuate due to a number of factors. TSH levels may show marked variation depending on the time when they are measured. So, daytime testing is usually preferred. Elevated TSH levels have also been observed with aging and during the cold winter months. Total T3 & T4 concentrations are also altered by changes in thyroid binding protein levels. In such cases, levels of free T4, free T3 may be advised.

Q. What are the symptoms of thyroid disorders?

Symptoms of thyroid disorders can vary depending on whether the thyroid gland is overactive (hyperthyroidism) or underactive (hypothyroidism). Common symptoms of hyperthyroidism include weight loss, nervousness, irritability, increased sweating, and rapid heartbeat, and signs of hypothyroidism include weight gain, fatigue, sensitivity to cold, constipation, and dry skin.

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