t3 peptide FAQ

A T3 test is quite simple and doesn’t require any special preparation, such as overnight fasting. Unless your doctor says otherwise — perhaps you’re having other blood tests at the same time — you usually should eat as you would normally because fasting could affect your results. Research hasn’t shown a link between T3 levels and fasting, but fasting can influence TSH levels in your body. Before you go for the test, you need to tell your doctor about any medications and nonprescription supplements you’re taking, as some can affect thyroid hormone levels. Your doctor will tell you if you need to stop taking them beforehand and, if so, how far in advance.

It is an ordinary blood test, where blood is taken from your arm using a small needle. It generally takes less than five minutes and has little risk involved. You may feel some pain or get some bruising after. The tenderness should go away within a few hours, but it could take a few days for the bruise to disappear.

There are several medications and even some supplements that can affect the results of thyroid function tests. It’s important to tell your doctor about all drugs you take, including prescription, over-the-counter, supplemental, and recreational drugs, before having a thyroid function test.

Some medications can affect the results of a T3 test. They include:‌

T3 isn’t a routine test because the TSH test is more sensitive and tells your doctor more than just the T3 alone. A T3 test is usually done only if your doctor suspects hyperthyroidism or wants to check how well your thyroid medications are working.

T3 should not be used to help lose weight. It is a hormone given in very precise doses that can cause serious or life-threatening issues if not used as directed.

There are no risks to having a blood test to check your T3 levels. You might have some bruising or tenderness at the area where the blood was drawn, but these should go away within a few days.

A TSH test measures how much of this hormone is in your blood. TSH is made by your pituitary gland, a small gland in your brain that tells your thyroid how much hormone to make. Your doctor may order this test to:

If you’re experiencing hyperthyroidism symptoms, your doctor might suggest you have a T3 test. “If your screening or TSH levels are normal but you still have symptoms of a thyroid disorder, talk to your doctor about free T3 testing,” Barrera says. Other reasons to have a T3 test include:

There are several reasons why someone may have abnormal T3 results.

Facilities and clinics may have their own labs on-site, or they might send the blood to an outside lab for testing, so timing for results can vary. The usual time to wait for T3 results is one to two business days.

Your doctor will decide if you need to have your T3 levels checked. It might be done if you show signs of hyperthyroidism or if you’re already receiving medication to manage a thyroid problem.

T3 makes up 10% of all hormones released by the thyroid. There are two forms of T3: free and bound. Most of the T3 in your blood is attached, or bound, to proteins, and only a small percentage of it is free. A total T3 test measures both bound and free T3. A free T3 test measures the amount of free T3, the active hormone that your body can use as needed. The free T3 test is usually more helpful because it directly measures the hormone that is active in your body. The other thyroid hormone is T4. As it moves through your blood, your body changes it into T3 when you need it. Most of this happens in your liver and kidneys. “T4 is like money in your bank account and T3 is like the money in your wallet,” says Joseph Barrera, MD, an endocrinologist at Providence Mission Hospital in Mission Viejo, California. T3 is what you use right away, and T4 is what you can draw on when you need more T3.