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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

Earliest reports in

12 hours

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) is a set of blood tests that measure the levels of thyroid-stimulating hormone (TSH), thyroxine hormone (T4), and triiodothyronine hormone (T3) to assess thyroid function. Together, these tests help identify how well the thyroid gland works.

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

The doctor may advise this test if there are symptoms suggestive of thyroid disorders, such as hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid).

Some common symptoms of hypothyroidism include:

Weight gain
Anxiety
Fatigue
Sensitivity to cold
Constipation
Dry skin
Frequent or heavy menstrual periods

Some common symptoms of hyperthyroidism include:

Weight loss
Sensitivity to warm temperature
Irritability
Hand tremors
Increased sweating
Rapid heartbeat
Hair loss
Changes in menstrual periods, often lighter and/or less frequent

Doctors also recommend Thyroid Profile Total (T3, T4 & TSH) for women during pregnancy to check if they have adequate amounts of thyroid hormones. These hormones are important for fetal brain development and pregnancy health.

The levels of thyroid hormones (T3 and T4) hormones fluctuate due to changes in a protein called thyroxine-binding globulin (TBG). TBG helps carry thyroid hormones to the right parts of the body. The level of TSH can vary, depending on factors like the time of day it is tested. That is why it's better to test TSH in the daytime for more accurate results.

No special preparations are needed for this profile. Usually, you do not need to discontinue taking thyroid medication before getting tested. However, inform your doctor about all the medications being taken, as some of them might affect the test results.

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

Lifestyle Tips for Optimal Thyroid Hormone Levels:

🥤Hydration: Stay hydrated. Dehydration can temporarily alter thyroid hormone levels.

🥗Eat (Diet): Eat at least five portions of a variety of fruits and vegetables every day. Eat iodine-rich foods and avoid long-term consumption of soy.

🚴‍♀️Activity (Exercise): Exercise helps manage symptoms like weight changes, mood changes, and improves overall thyroid health.

😴Lifestyle (Stress and Sleep): Practice yoga, meditation, or deep breathing, and prioritize quality sleep—both stress and sleep are vital for thyroid hormone balance.

👨‍⚕️Talk to Your Doctor (Consult): Do not self-medicate. Always consult your doctor before starting, stopping, or changing doses of thyroid medication.

🚭Habits (Alcohol and Smoking): Avoid smoking and limit excessive alcohol consumption as these habits can impair thyroid function.

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

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

A. In Symptomatic Individuals

1) Hyperthyroidism

Weight loss
Rapid or irregular heartbeat
Trouble sleeping
Sweating or being very sensitive to heat
Fertility problems in women

2) Hypothyroidism

Weight gain
Being very sensitive to cold
Dry, thin hair
Heavy or irregular menstrual periods
Fertility problems in women

B. In High-Risk Groups

Personal history or strong family history of thyroid disorders
Past history of neck irradiation
Previous thyroidectomy or radioactive iodine ablation
History of autoimmune disorders

C. In Special Population

Pregnancy
Elderly individuals
Newborns (for congenital hypothyroidism screening)

D. In Individuals With Lifestyle-Related Risks

Follow a low iodine intake
Prolonged high-soy diet
Selenium deficiency

E. In Individuals With Certain Health Conditions

Thyroiditis
Damage to the pituitary gland
Congenital hypothyroidism

F. In Routine Follow-Ups

After adjusting thyroid medication dosage
To evaluate the effectiveness after radioactive thyroid treatment

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

Contains 3 tests

The Thyroid Profile Total (T3, T4 & TSH) measures the levels of triiodothyronine hormone (T3) total, thyroxine hormone (T4) total, and thyroid-stimulating hormone (TSH) in the blood. Thyroid hormones (T3 and T4) and TSH work in opposite ways. When T3 and T4 levels go up, TSH levels usually go down, and when T3 and T4 go down, TSH goes up. This happens due to the pituitary-thyroid feedback mechanism:

In hypothyroidism (low levels of T3 and T4), the pituitary gland responds by increasing TSH secretion to stimulate the thyroid gland.

In hyperthyroidism (elevated T3 and T4 levels), TSH secretion is suppressed to decrease thyroid activity.

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 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, the Thyroid Profile Total (T3, T4 & TSH) can show variable results due to several 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, sensitivity to warm temperatures, increased sweating, rapid heartbeat, menstrual period changes, etc. Common symptoms of hypothyroidism include weight gain, fatigue, sensitivity to cold, constipation, dry skin, heavy or irregular menstrual periods, fertility problems in women, etc.

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