HbA1c blood test
HbA1c · A1C test · glycated hemoglobin · 3-month blood sugar test
A blood test that shows your average blood sugar over the last 2 to 3 months. One short spike in sugar barely affects it.
To find diabetes or prediabetes, and to check how treatment is working if you already have diabetes.
⏱ Duration: usually 5 minutes; blood is taken from a vein
Be sure to tell your doctor
How to prepare
- Food. Usually you do not need an empty stomach. You can have the test at any time. If you also have a blood sugar test, come in the morning before eating.
- Medicines. Take your medicines as usual. If you are not sure, tell your doctor. They will decide.
What to bring
- Your referral, if you have one
- Past results of this test, to compare
How it goes
- You sit down and rest your arm on the armrest
- A band is tied above your elbow
- The skin is wiped, and blood is taken from a vein into a tube
- A cotton ball is pressed on the spot
What you'll feel
- A quick prick, like a mosquito bite
- Sometimes a small bruise is left afterwards
Afterwards
- You can eat and go back to your usual day right away
- Results usually take 1 to 2 days
- Your doctor explains the result and compares it with normal levels and your past tests
Common questions
Do I need an empty stomach for an HbA1c test?
Usually not. It shows your sugar over 2 to 3 months, so breakfast barely affects the result.
How often should I have this test if I have diabetes?
Usually every 3 months if your treatment is being changed. When your sugar is stable, less often. Your doctor will give you the exact schedule.