National Institutes of Health

Effects of Marijuana on Bodies and Brains

These are just some of the problems marijuana can cause:

Memory Problems

Marijuana makes it hard to remember things that just happened a few minutes ago. That makes it hard to learn in school or to pay attention to your job. A recent study showed that if you begin regular marijuana use as a teen, you can lose an average of 8 IQ points, and do not get them back, even if you stop using the drug.

Heart Problems

Using marijuana makes the heart beat fast and raises your risk of having a heart attack.

Coughing and Breathing Problems

Marijuana smokers can get some of the same coughing and breathing problems as cigarette smokers. Marijuana smoke can hurt your lungs.

Drugged Driving

Driving when you're high on marijuana is dangerous, just like driving drunk. Your reactions to traffic signs and sounds are slow. It's hard to pay attention to the road. And it's even worse when you're high on marijuana and alcohol at the same time.

You Stop Caring

Over time, marijuana users can get "burnt out." They don't think about much or do much. They can't concentrate. They don't seem to care about anything.

Addiction

Although some people don't know it, you can get addicted to marijuana after using it for a while. This is more likely to happen to people who use marijuana every day, or who started using it when they were teenagers.

Woman coughing

Marijuana smoke can hurt your lungs and cause some of the same coughing and breathing problems faced by cigarette smokers. (Photo information)