People use drugs for many reasons: they want to feel good, stop feeling bad, or perform better in school or at work, or they are curious because others are doing it and they want to fit in. The last reason is very common among teens.
Drugs excite the parts of the brain that make you feel good. But after you take a drug for a while, the feel-good parts of your brain get used to it. Then you need to take more of the drug to get the same good feeling. Soon, your brain and body must have the drug to just feel normal. You feel sick, awful, anxious, and irritable without the drug. You no longer have the good feelings that you had when you first used the drug. This is true if you use illegal drugs or if you misuse prescription drugs. Misuse includes taking a drug differently than how your doctor tells you to (taking more or crushing pills to “shoot up” or snort), taking someone else’s prescription, or taking it just to get “high.”