Drugs are chemicals that change the way a person's body works. You've probably heard that drugs are bad for you, but what does that mean and why are they bad?

Medicines Are Legal Drugs
If you've ever been sick and had to take medicine, you already know about one kind of drugs. Medicines are legal drugs, meaning doctors are allowed to prescribe them for patients, stores can sell them, and people are allowed to buy them. But it's not legal, or safe, for people to use these medicines any way they want or to buy them from people who are selling them illegally. 

Cigarettes and Alcohol
Cigarettes and alcohol are two other kinds of legal drugs. (In the United States, adults 18 and over can buy cigarettes and those 21 and over can buy alcohol.) But smoking and excessive drinking are not healthy for adults and off limits for kids.

Illegal Drugs
When people talk about the "drug problem," they usually mean abusing legal drugs or using illegal drugs, such as marijuana, ecstasy, cocaine, LSD, and heroin. (Marijuana is generally an illegal drug, but some states allow doctors to prescribe it to adults for certain illnesses.)   

Why Are Illegal Drugs Dangerous?
Illegal drugs aren't good for anyone, but they are particularly bad for a kid or teen whose body is still growing. Illegal drugs can damage the brain, heart, and other important organs. Cocaine, for instance, can cause a heart attack - even in a kid or teen. 

While using drugs, a person is also less able to do well in school, sports, and other activities. It's often harder to think clearly and make good decisions. People can do dumb or dangerous things that could hurt themselves - or other people - when they use drugs.

Why Do People Use Illegal Drugs?
Sometimes kids and teens try drugs to fit in with a group of friends. Or they might be curious or just bored. A person may use illegal drugs for many reasons, but often because they help the person escape from reality for a while. If a person is sad or upset, a drug can - temporarily - make the person feel better or forget about problems. But this escape lasts only until the drug wears off.

Drugs don't solve problems, of course. And using drugs often causes other problems on top of the problems the person had in the first place. A person who uses drugs can become dependent on them, or addicted. This means that the person's body becomes so accustomed to having this drug that he or she can't function well without it. 

Once a person is addicted, it's very hard to stop taking drugs. Stopping can cause withdrawal symptoms, such as vomiting (throwing up), sweating, and tremors (shaking). These sick feelings continue until the person's body gets adjusted to being drug free again. 

Can I Tell If Someone Is Using Drugs?
If someone is using drugs, you might notice changes in how the person looks or acts. Here are some of those signs, but it's important to remember that depression or another problem could be causing these changes. A person using drugs may: 

• lose interest in school
• change friends (to hang out with kids who use drugs)
• become moody, negative, cranky, or worried all the time
• ask to be left alone a lot
• have trouble concentrating
• sleep a lot (maybe even in class)
• get in fights
• have red or puffy eyes
• lose or gain weight
• cough a lot
• have a runny nose all of the time

What Can I Do to Help?
If you think someone is using drugs, the best thing to do is to tell an adult that you trust. This could be a parent, other relative, teacher, coach, or school counselor. The person might need professional help to stop using drugs. A grown-up can help the person find the treatment he or she needs to stop using drugs. Another way kids can help kids is by choosing not to try or use drugs. It's a good way for friends to stick together. 

Understanding drugs and why they are dangerous is another good step for a kid to take. Below, we've listed some words that may be new to you.

Words to Know
Addiction (say: uh-dik-shun) - A person has an addiction when he or she becomes dependent on or craves a drug all of the time. 

Depressant (say: dih-preh-sunt) - A depressant is a drug that slows a person down. Doctors prescribe depressants to help people be less angry, anxious, or tense. Depressants relax muscles and make people feel sleepy, less stressed out, or like their head is stuffed.  Some people may use these drugs illegally to slow themselves down and help bring on sleep - especially after using various kinds of stimulants. (See below.)

Hallucinogen (say: huh-loo-sun-uh-jun) - A hallucinogen is a drug, such as LSD, that changes a person's mood and makes him or her see, hear, or think things that aren't really there.

High - A high is the feeling that drug users want to get when they take drugs. There are many types of highs, including a very happy or spacey feeling or a feeling that a person has special powers, such as the ability to fly or to see into the future.

Inhalant (say: in-hay-lunt) - An inhalant, such as glue or gasoline, is sniffed or "huffed" to give the user an immediate rush. Inhalants produce a quick feeling of being drunk - followed by sleepiness, staggering, dizziness, and confusion.

Narcotic (say: nar-kah-tik) - A narcotic dulls the body's senses (leaving a person less aware and alert and feeling carefree) and relieves pain. Narcotics can cause a person to sleep, fall into a stupor, have convulsions, and even slip into a coma. Certain narcotics - such as codeine - are legal if given by doctors to treat pain. Heroin is an illegal narcotic because it is has dangerous side effects and is very addictive.

Stimulant (say: stim-yuh-lunt) - A stimulant speeds up a person's body and brain. Stimulants, such as methamphetamines and cocaine, have the opposite effect of depressants. Usually, stimulants make a person feel high and energized. When the effects of a stimulant wear off, the person will feel tired or sick.

Updated and reviewed by: Robert B. Lembersky, MD
Date reviewed: May 2004
Originally reviewed by: Steven Dowshen, MD, and Jonathan Schneider, DO