OVERVIEW
Thyroxine test also known as T4 helps to evaluate thyroid function and diagnose thyroid diseases. This test is performed if your body shows symptoms of:
Hyperthyroidism
Hypothyroidism
If TSH (Thyroid-stimulating Hormone) levels are abnormal
FREQUENTLY ASKED QUESTIONS (FAQS)
How is this test performed?
This test is performed on a blood sample. The blood is obtained from the vein and this is performed by a healthcare provider in the following way.
- clean the skin
- put an elastic band above the area
- insert a needle into a vein (usually in the arm inside of the elbow or on the back of the hand)
- pull the blood sample into a vial or syringe
- take off the elastic band and remove the needle from the vein
Are there any risks associated with it?
There are many risks related to thyroxine hormone, which if not treated well can cause serious health issues. Whereas there are no much risks related to the test, it’s a minor procedure which can only cause minor bruise or soreness at the site of injection.
WHAT DOES TEST MEASURES?
The result of the T4 lab test alone cannot give any definite diagnosis, a series of tests are performed alongside to get a clear conclusion.
Thyroxine ( T4): A high level of Thyroxine (T4) indicates an overactive thyroid (hyperthyroidism) and a low level of Thyroxine (T4) indicates an underactive thyroid (Hypothyroidism).
T4 Range: 4.6-12 ug/dl
WHY GET TESTED?
This test is done to give knowledge of how well the Thyroid gland is working in the body. The T4 test is ordered if you observe symptoms of Hyperthyroidism or Hypothyroidism.
Symptoms of Hyperthyroidism may include:
- Increased heart rate
- Anxiety
- Weight loss
- Difficulty sleeping
- Tremors in the hands
- Weakness
- Diarrhea (sometimes)
- Light sensitivity, visual disturbances
- There may be puffiness around the eyes with dryness, irritation, and, in some cases, bulging of the eyes.
- Menstrual irregularity in women
Symptoms of hypothyroidism may include:
- Weight gain
- Dry skin
- Constipation
- Cold intolerance
- Puffy skin
- Hair loss
- Fatigue
- Menstrual irregularity in women
