Overview

Bruises form when small blood vessels under the skin tear or rupture, most often from a bump or fall. Blood leaks into tissues under the skin and causes the black-and-blue colour. As bruises (contusions) heal, they often turn colours, including purplish black, reddish blue, or yellowish green. They usually heal within 2 to 4 weeks. Sometimes the area of the bruise spreads down the body in the direction of gravity. A bruise on a leg usually will take longer to heal than a bruise on the face or arms.

Most bruises aren't a cause for concern. They will go away on their own. Home treatment may speed healing and relieve the swelling and soreness from bruises that are caused by injury. But severe bruising, swelling, and pain that start within 30 minutes of an injury may mean a more serious problem, such as a severe sprain or fracture.

If you bruise easily, you may not even remember what caused a bruise. Bruising easily doesn't mean you have a serious health problem, especially if bruising is minimal or only shows up once in a while.

• Older adults often bruise easily from minor injuries. Bruises are most common in injuries to the forearms, hands, legs, and feet. As a person ages, the skin becomes less flexible and thinner because there is less fat under the skin. The cushioning effect of the skin decreases as the fat under the skin decreases. These changes, along with skin damage from exposure to the sun, cause blood vessels to break easily. When blood vessels break, bruising occurs.
• Women bruise more easily than men, especially from minor injuries on the thighs, buttocks, and upper arms.
• A tendency to bruise easily sometimes runs in families.

In some cases after an injury, blood collects and pools under the skin (hematoma). This gives the skin a spongy, rubbery, lumpy feel. A regular bruise is more spread out. It may not feel like a firm lump. A hematoma usually isn't a cause for concern. It's not the same thing as a blood clot in a vein. And it doesn't cause blood clots.

Bruises that don't seem to be caused by an accidental injury may be caused by abuse. It's important to consider this possibility, especially if the bruises can't be explained or if the explanations change or don't match the injury. Report this type of bruising, and seek help to prevent further abuse.

Blood spots

Blood spots under the skin may be either purpura or petechiae. Purpura might look like bruises, but they aren't caused by an injury as most regular bruises are. Petechiae don't look like bruises. They are tiny, flat, red or purple spots in the skin. But they are different than the tiny, flat, red spots or birthmarks (hemangiomas) that are on the skin all the time.

Some people have sudden unexplained bruising or blood spots under the skin, or they may suddenly get bruises more often. This may be caused by:

• A medicine, such as aspirin or blood thinners (anticoagulants).
• An infection that causes the buildup of toxin in the blood or tissues (sepsis).
• A bleeding or clotting disorder, such as hemophilia, von Willebrand disease, thrombocytopenia, or another less common bleeding or clotting disorder.
• Other diseases that affect clotting. Examples include:
  • Chronic inflammatory diseases, such as lupus.
  • Liver disease, such as cirrhosis.
  • Some types of cancer, such as Hodgkin lymphoma, leukemia, or multiple myeloma.
• Inflammation of a blood vessel (vasculitis).
• Malnutrition, such as deficiencies of vitamins B12, C, or K, or folate.

Medical treatment for abnormal bruising or blood spots focuses on preventing or stopping bleeding, changing or adjusting a medicine that may be causing the bruising, or treating the medical problem that is causing the bruising.

If the skin is injured over a bruise, be sure to watch for signs of a skin infection.

Self-Care

You may be able to use home treatment to help relieve pain, swelling, and stiffness.

• Rest.

  It's important to rest and protect the bruised area.

• Use ice.

  Ice will reduce pain and swelling. Apply ice or cold packs right away to prevent or reduce swelling. Apply the ice or cold pack for 10 to 20 minutes, 3 or more times a day.

  • For the first 48 hours after an injury, avoid things that might increase swelling. These things include hot showers, hot tubs, hot packs, and drinks that contain alcohol.
  • After 48 to 72 hours, if swelling is gone, apply heat. You can start gentle exercise with the aid of moist heat to help restore and maintain flexibility. Some experts recommend switching between hot and cold treatments.
• Wrap the bruised area.

  Compression, or wrapping the bruised area with an elastic bandage (such as an Ace wrap), will help reduce swelling. Don't wrap it too tightly, because that can cause more swelling below the affected area. Loosen the bandage if it gets too tight. Signs that the bandage is too tight include numbness, tingling, increased pain, coolness, or swelling in the area below the bandage.

• Elevate the bruised area.

  Try to keep the area at or above the level of your heart to help reduce swelling. Prop up the bruised area on pillows while you apply ice and anytime you sit or lie down.

• Rub the area.

  Gently massage or rub the area to relieve pain and encourage blood flow. But don't massage the bruised area if it causes pain.

• Use pain medicines.

  Be safe with medicines. Read and follow all instructions on the label. If the doctor gave you a prescription medicine for pain, take it as prescribed. If you are not taking a prescription pain medicine, ask your doctor if you can take an over-the-counter medicine.

• Think about using alternative medicine.

  If you'd like, apply a natural health product directly to the bruise.

  • Witch hazel may help heal damaged veins.
  • Arnica may stimulate healing.
• Do not use tobacco.

  Don't smoke or use other tobacco products. Smoking slows healing because it decreases blood supply and delays tissue repair.

If you need to use a wrap for more than 48 hours, you may have a more serious injury that needs to be checked by a doctor.

When to call for help during self-care

Call a doctor if any of the following occur during self-care at home:

• New or worse signs of infection, such as redness, warmth, swelling, pus, or a fever.
• Symptoms occur more often or are more severe.

Preparing For Your Appointment