It’s normal to get a little bruise after having your blood drawn. A bruise is usually caused by small blood vessels accidentally damaged when your healthcare provider inserts the needle. A bruise could also occur if the needle were not removed with enough pressure.
Most bruises after a blood draw are not serious and don’t need treatment. If your bruises are severe, or if you have bleeding from other areas, it may be an indication of a more serious condition.
Common causes of bruises following a blood draw
Bruising is also known as Ecchymosis. It occurs when capillaries under the skin become damaged. This causes bleeding below the skin. Blur is the result of blood clots under the skin’s surface.
Blood vessels can be damaged.
A blood draw is when a healthcare provider who has been specially trained in collecting blood, such as a phlebotomist, or nurse, inserts a needle into the vein. This usually happens on your wrist or elbow.
The needle may cause damage to some capillaries during its induction, which can lead to bruising. These small blood vessels are not always visible, so it is not necessarily the fault.
The needle may need to be repositioned following the initial placement. The person drawing blood might place the needle too far into the vein.
Veins that are small and difficult to find
More likely, blood vessels are damaged if the person drawing blood has difficulty finding a vein. This is sometimes called “a difficult stick”.
Although they will normally take time to find the best vein, sometimes it is impossible.
There is not enough pressure after
A person who draws blood too quickly after removing the needle may cause bruising. This situation increases the chance of blood leaking into surrounding tissues.
Other causes of bleeding after blood draws.
If you are:
- Take anticoagulants to reduce blood clotting such as aspirin, Warfarin (Coumadin), or Clopidogrel (Plavix).
- Take nonsteroidal anti-inflammatory drugs (NSAIDs ) for pain relief, such as ibuprofen, Motrin, or naproxen (Aleve).
- Supplements such as fish oil and ginger may reduce the body’s ability to clot.
- You have another medical condition that causes you to bruise easily. This includes Cushing Syndrome, kidney disease, liver disease, kidney disease, hemophilia or von Willebrand Disease.
Older adults might also be more likely to bruise because their skin is thinner.
A bruise that forms after a blood test is usually not causing concern. If you notice any bruising in other areas of your body, or if the bruises are very large, there may be another reason.
How to avoid bleeding after a blood draw
After a blood draw, you can’t avoid bruising. Some people bruise more easily than others.
There are steps you can take to avoid bruising if you have to have your blood drawn.
- Avoid using any medication that could cause blood thinning within the 24 hours following your appointment.
- Do not carry any heavy items, such as a handbag. You must use that arm for several hours following the blood draw. Lifting heavy objects can cause pressure on the needle site, leading to a blood clot.
- During the blood draw, wear loose-fitting sleeves and a top.
- After removing the needle, apply firm pressure and keep the bandage on for several hours.
- Apply a cold compress to the area where you see a bruise and raise your arm to speed up the healing process.
If you have bruises from blood drawn, tell your doctor. It would be best if you also informed them about any medical conditions and medications that can cause problems with clotting.