Ever donated blood and got a bruise?


Although we hope that no one will have any ill effects from giving blood, occasionally bruising of the arm and some arm pain may develop.

See previous post.

Although we hope that no donor will have any ill effects from giving blood, occasionally bruising of the arm may develop. The bruise can look very dramatic and some
people may find this worrying, especially if it is not visible until the next day. Bruising can look very nasty, but it is usually harmless and will disperse with time.

What is bruising?
Bruising is caused by bleeding under the skin. The blood usually collects in the area as a bruise although gravity may cause the bruise to appear away from the donation site. With time the familiar blue-black discolouration changes to green, then yellow and eventually fades and disappears. This may take up to three weeks or more if the bruise is large and swollen.

Why can it happen with blood donation?
When the needle is taken out of the arm bleeding will continue until the small hole in the vein closes up. The way to prevent this is to apply pressure to the arm, over the site where the needle was inserted, until all signs of bleeding have stopped. Failure to maintain this pressure is the most common cause of bruising.

If a bruise occurs during blood donation, the process may be discontinued to prevent it from worsening. With time, the familiar blue-black discolouration changes to green, then yellow and eventually fades and disappears. This may take two to three weeks if the bruise is large. It is normal for bruises to spread out before fading.

During or after blood donation, the following may happen:

  • The vein is pierced during blood donation, causing some blood to leak into the surrounding tissue. The donor is more likely to develop a bruise if the venepuncture procedure was more difficult than usual.
  • There are tiny fragile blood vessels running just under the skin, as well as the larger veins from which the blood donation is obtained. When the donation needle is inserted into the arm, one of these small vessels may be injured and bleeding occurs.
  • Inadequate pressure placed on the venepuncture site after removal of the needle may allow blood to leak in the surrounding tissues.
  • Lifting heavy objects after blood donation could put pressure on the venepuncture site and dislodge the clot formed.

Prevention and management of bruising following blood donation

  • Wear clothes with loose fitting sleeves when donating blood. A tight sleeve can act as a tourniquet and cause congestion in the vein, increasing the chance of bruising.
  • Apply firm pressure to the venepuncture site after donation, as advised by the Blood Bank staff member, until the bleeding has stopped. A plaster will be applied to cover the venepuncture site; this should be kept on for a minimum of six hours.
  • Avoid lifting heavy objects for a few days as this could aggravate the bruising. However, gentle movements are recommended whilst the bruise is healing.
  • If bruising has developed, applying cold compresses to the area can also help to relieve any pain or discomfort.
  • If you require more pain relief, it is recommended to take paracetamol (according to the manufacturer’s instructions); avoid taking aspirin or ibuprofen for the first 24 hours.
  • If you experience any of the following, seek further help or call National Blood Transfusion Service (Blood Bank) on 427 7192 for advice:
    — Severe pain
    — Numbness or persistent ”pins and needles” in the arm, hand or fingers
    — Swelling which is large or increasing in size
    — Painful redness and inflammation.


    Treat your bruise with R.I.C.E

    Rest – allow time for the arm to heal, avoid heavy lifting, e.g. at the gym or carrying heavy shopping. Light gentle movement is recommended. After 36 hours, return to normal activity.

    Ice – This is most effective immediately for swelling of the bruise and surrounding area. Do not place directly onto the skin; use a cloth to act as a barrier to prevent freezeburns, e.g. pack of frozen vegetables or an ice pack.

    Compression – pressing on the point where the needle was inserted.

    Elevation – If possible, when resting elevate your arm on a pillow.

    Treatment for the bruise is most effective whilst the bruise is still reddish, however after 36 hours – heat in the form of a warm cloth to be applied to the bruise for approximately 10 minutes, 2-3 times a day may increase blood flow to the bruised area allowing the skin to reabsorb the bruise more quickly – ultimately the bruise will fade in colour.

    Resources: 1. WHO – https://www.ncbi.nlm.nih.gov/books/NBK310575/
                          2. Blood Bank UK – https://www.blood.co.uk/the-donation-process/further-information/bruising-and-arm-pain/