Thyroid Function Test

A healthcare provider may advise TFTs to diagnose various thyroid conditions such as:

• Hyperthyroidism (overactive thyroid): Symptoms of hyperthyroidism are:
  • Anxiety
  • Weight loss
  • Increased heart rate
  • Weakness
  • Diarrhoea
  • Difficulty in sleeping
  • Tremors
  • Puffiness around the eyes
  • Hypothyroidism (underactive thyroid):
• Hypothyroidism (underactive thyroid): Symptoms of hypothyroidism are:
  • Sudden weight gain
  • Constipation
  • Dryness of the skin
  • Fatigue
  • Loss of hair
  • Intolerance to cold
  • Puffiness of the skin
  • Irregularity in menstrual cycle in females

• Graves’ disease
  • An autoimmune disorder that causes hyperthyroidism
• Hashimoto’s disease
  • An autoimmune disorder in which the thyroid gland is destroyed gradually
• Thyroid Nodules
  • Solid or fluid-filled lumps within the thyroid gland (Read more: Thyroid nodules treatment)

• Thyroid cancer
• TFTs may also need to be done under the following conditions:
  • If an individual is on thyroid hormone replacement treatment
  • For women who test positive for infertility

No specific preparation is usually needed for this test. It can be done at any time of the day, and no fasting is required to take this test. However, some medicines can alter the result of thyroid function tests, so it’s better to inform the doctor if you are taking any prescription or non-prescription medication.

To perform this test, a blood sample is drawn from a vein in the arm with the help of a needle. The process is painless and non-invasive, but some patients may experience slight redness in the area of needle puncture. Redness can be minimised by placing an ice pack over the affected area.

Normal results:

Following is the normal range for thyroid hormone levels:

• TSH: 0.4-4.0 mU/L (milliunits per litre)
• Free T4: 9.0-25.0 pmol/L (picomoles per litre)
• Free T3: 3.5-7.8 pmol/L 

Abnormal results:

If thyroid gland is not functioning properly, it can result in an increased or decreased level of thyroid hormones. Increased TSH concentration can be a sign of hyperthyroidism and decreased TSH concentration could be a sign of hypothyroidism.

TSH will probably be tested first. If it is abnormal, other tests will be done to get further clarity about your condition.

High TSH level can be due to the following conditions:

• Hypothyroidism
• Dysfunction of the pituitary gland
• Inadequate dose of thyroid hormone medication for the treatment of hypothyroidism.

Low TSH level can be due to the following conditions:

• Hyperthyroidism
• The dose of thyroid hormone medication for the treatment of hypothyroidism is more than required.

Other than TFTs, the following tests can be used to diagnose thyroid disorders:

• Ultrasound
• Thyroid scan
• Radioactive iodine uptake test

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. This information is purely from an educational point of view and is in no way a substitute for medical advice by a qualified doctor.

Call this no. to book this test - 9818293792