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Bruises

What Is a Bruise?

A bruise, also called a contusion (pronounced: kun-TOO-zhen), happens when a part of the body is injured and blood from the damaged capillaries (small blood vessels leaks out. With no place to go, the blood gets trapped under the skin, forming a red or purplish mark that's tender when you touch it — a bruise.

Bruises can happen for many reasons, but most are the result of bumping and banging into things — or having things bump and bang into you. Fortunately, as anyone who's ever sported a shiner knows, the mark isn't permanent.

How Long Do Bruises Last?

Bruises usually fade away in about 2 weeks. Over that time, the bruise changes color as the body breaks down and reabsorbs the blood. The color of the bruise can give you an idea how old it is:

  • When you first get a bruise, it's kind of reddish as the blood appears under the skin.
  • Within 1 or 2 days, the hemoglobin (an iron-containing substance that carries oxygen) in the blood changes and your bruise turns bluish-purple or even blackish.
  • After 5 to 10 days, the bruise turns greenish or yellowish.
  • Then, after 10 or 14 days, it turns yellowish-brown or light brown.

Finally, after about 2 weeks, your bruise fades away.

Who Gets Bruises?

Anyone can get a bruise. Some people bruise easily, while others don't. Why? Bruising depends on several things, such as:

  • how tough the skin tissue is
  • whether someone has certain diseases or conditions
  • whether a person's taking certain medications

Also, blood vessels tend to become fragile as people get older, which is why elderly people tend to bruise more easily.

How Can I Help Myself Feel Better?

Apply a cold compress to the bruise to help slow down the blood that's flowing to the area, which decreases the amount of blood that ends up leaking into the tissues. It also helps keep the inflammation and swelling down. All you have to do is apply cold to the bruise for 15 to 20 minutes every hour for a day or two after the bruise appears.

You don't need to buy a special cold pack, although they're great to keep on hand in the freezer. Just get some ice, put it in a plastic bag, and wrap the bag in a cloth or a towel and place it on the bruise (don't apply the ice directly to the skin).

Another trick is to use a bag of frozen vegetables. It doesn't matter what kind — carrots, peas, lima beans, whatever — as long as they're frozen. A bag of frozen vegetables is easy to apply to the bruise because it can form to the shape of the injured area. Also, like a cold pack, it can be used and refrozen again and again (just pick your least-favorite vegetables and label the bag — you don't want to keep thawing and freezing veggies that you plan to eat!).

To reduce swelling and bruising, elevate the bruised area above the level of your heart. In other words, if the bruise is on your shin, lie down on a couch or bed and prop up your leg. This will help prevent blood from pooling in the area because more of the blood will flow back toward your heart. If you keep standing, more blood will flow to your bruised shin and the bruise will be larger.

Take acetaminophen for pain, if needed.

When Should I Call the Doctor?

Minor bruises are easily treated, but it's probably best to talk to a doctor if:

  • A bruise isn't improving after 2 weeks.
  • You bruise often and bruises seem to develop for no known reasons.
  • Your bruise is swelling and very painful.
  • You can't move a joint or you think you may have a broken bone.
  • The bruise is near your eye and you have difficulty moving your eyes or seeing.

Can Bruises Be Prevented?

Bruises are kind of hard to avoid completely. But if you're playing sports, riding your bike, inline skating, or doing anything where you might bump, bang, crash, or smash into something, it's smart to wear protective gear like pads, shin guards, and helmets. Taking just a few extra seconds to put on that gear might save you from a couple of weeks of aches and pains.

Reviewed by: Mary L. Gavin, MD
Date reviewed: August 2018