When you swallow a pain reliever (either as a liquid or a pill), do you have to tell it to go to your head, your ear or your shin? Nope!
The medicine in a pain reliever doesn't go directly to whatever part of your body is hurting. Instead, pain relievers work by going everywhere.
After you swallow a pain reliever, it goes to your stomach where it's digested and absorbed into your bloodstream. Once it gets in your blood, the medicine travels throughout your whole body.
So how does this help that one spot where you're hurting feel better?
When cells in your body become injured or damaged, they release a chemical called "prostaglandin" (pross-tuh-GLAN-din). Your body's nerve endings are very sensitive to prostaglandin.
When they sense a release of prostaglandin, your nerve endings transmit a message through the nervoussystem to your brain, telling it where and how much an area of the body hurts. Pain relievers work — all throughout the body — by preventing injured cells from releasing prostaglandin.
When cells stop releasing prostaglandin, the nervous system stops sending pain messages to the brain. When the brain stops receiving pain messages, you stop feeling pain.
But pain isn't always bad, even if it doesn't feel very good. Pain is your body's way of warning you that something is wrong so you can fix it.
If you didn't feel pain, you might not realize that there was a problem, and it could get much worse before you notice it on your own.