What is a bruise?

A bruise is a spot on your skin that looks blue, purple, or yellow after you bump or fall. It happens when tiny tubes that carry blood under your skin (they are like very small water pipes) get a little hurt and some blood leaks out under the skin. The blood doesn’t come out of your body — it stays under the skin like a colorful patch.

Step-by-step: How a bruise forms

1. You bump yourself. Maybe you hit a table or fall while playing.
2. Little blood vessels break. Tiny tubes under the skin tear a bit and let out a little blood.
3. The blood sits under the skin. That makes a dark spot that can be blue or purple at first.
4. Over days it changes color. The body is cleaning up the blood, and the bruise can turn green, yellow, or brown before it disappears.
5. It heals by itself. After some days or weeks the skin goes back to normal.

How you can feel better

• Tell a grown-up right away.
• Put something cold (like an ice pack wrapped in a towel) on the bruise for a little while soon after you bump it. This can help the swelling and pain. Don’t put ice directly on your skin.
• Rest and don't poke the bruise.
• If it's on an arm or leg, keeping it up a little can help (that is called "elevating").

When to tell a grown-up or see a doctor

Always tell a grown-up. They should call a doctor if:

• The bruise is very big or getting much bigger.
• The spot hurts a lot, or you can’t move the part of your body near it.
• The bruise doesn’t start to get better after a few days.
• You feel dizzy, very sleepy, or you hit your head hard.
• You get a lot of bruises and you don’t know why.

Remember: bruises are usually just your body fixing a little leak. They can look scary but they often get better by themselves. Always tell a grown-up so they can help you feel safe and comfortable.