Glycohemoglobin (HbA1c, A1c)
How To Prepare
You do not need to stop eating before
you have an A1c test. This test can be done any time during the day,
even after a meal.
How It Is Done
The health professional taking a sample
of your blood will:
- Wrap an elastic band around your upper arm to stop the flow of
blood. This makes the veins below the band larger so it is easier to put a
needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as the needle
- Put pressure on the site and then put on a bandage.
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
There is very little chance of a
problem from having blood sample taken from a vein.
- You may get a small bruise at the site. You can lower the
chance of bruising by keeping pressure on the site for several minutes.
- In rare cases, the vein may become swollen after the blood
sample is taken. This problem is called phlebitis. A warm compress can be used
several times a day to treat this.
- Ongoing bleeding can be a problem for people with bleeding
disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can
make bleeding more likely. If you have bleeding or clotting problems, or if you
take blood-thinning medicine, tell your doctor before your blood sample is
A1c is a blood test that
checks the amount of sugar (glucose) bound to
hemoglobin . The result is shown as a percentage. The
result of your A1c test can also be used to estimate your average blood sugar
level. This is called your estimated average glucose, or eAG. Your doctor will have your test results in a few days.