Finger-prick blood test
finger prick · finger stick · capillary blood test
A nurse makes a tiny prick on your fingertip and collects a few drops of blood. This is used for simple tests that need only a little blood.
For a complete blood count, blood sugar, in children, and when blood is hard to take from a vein.
⏱ Duration: usually 2 to 3 minutes
Be sure to tell your doctor
How to prepare
- Food. For blood sugar and many other tests, fast for 8 to 12 hours. Water is fine. Check with the lab.
- Hands. Come with warm hands. If they are cold, hold them under warm water. The blood will flow more easily.
- Medicines. Do not stop them on your own. If you take medicines in the morning, ask your doctor whether to take them before or after the test.
What to bring
- Your referral or list of tests
- Your ID
How it goes
- You sit down and rest your hand on the table
- Your finger is cleaned with antiseptic
- A quick prick on the side of the fingertip with a single-use lancet
- The first drop is wiped away, and the next drops go into a tube
- A cotton pad is pressed on your finger
What you'll feel
- A quick, sharp prick
- Your finger may ache a little for a couple of hours
Afterwards
- Keep the cotton pad pressed for 2 to 3 minutes
- Results usually come the same day or the next. The lab will tell you when
Common questions
Which is more accurate, blood from a finger or a vein?
For most tests, blood from a vein is more accurate. Finger-prick blood is used for simple tests, and it is enough for them.
Which finger do they prick?
Usually the ring or middle finger of the hand you use less. In small children, sometimes the heel.