Blood Drug Testing

Is it necessary to fast for a thyroid function blood test?

s it necessary to fast for a thyroid function blood test. if take any time this test what happen

Public Comments

1. No
2. A TSH test does not require fasting.
3. No. They're testing thyroid hormones. Eating wouldn't affect the results, like if you were getting a glucose test or a cholesterol panel might.
4. MY husband and daughter never does.
5. no, but if you are already on a synthetic thyroid replacement, it is best to take that day's dose after the blood work. I t can make the T4 numbers higher than they really are.
6. No, but if you test it frequently and you fast sometimes for it because you had a glucose or cholesterol, its best to test the same way each and every time. Make sure the test is first thing in the morning or its worthless. This is because TSH is highest while we sleep. You want to tes asap upon waking. By 2PM, TSH is at its lowest point of the day.