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Medical Marijuana - Topic Overview

What is medical marijuana and is it legal?

Medical marijuana is the use of this drug to help treat symptoms like pain, nausea, vomiting, and lack of appetite. It's often used by people with cancer, AIDS, multiple sclerosis, epilepsy, and other conditions.

It's against federal law to possess, sell, give away, or grow marijuana for any purpose. It's also against federal law for doctors to prescribe this drug. But more than a dozen states have passed state laws that allow people with certain health problems to buy or grow a limited amount of marijuana for their own use. Some states also allow or license people to provide medical marijuana to those who need it.

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If you use medical marijuana to treat approved medical conditions, the federal government might not prosecute you. But there's no guarantee that they won't.

Medical marijuana laws are different from state to state. If you think you might want to try medical marijuana, talk to your doctor. You can also call your state department of health or health services to learn more about the laws in your state.

What do the experts say?

The medical use of marijuana has been studied for decades. But experts still don't agree on how safe it is or how well it works.

Some medical experts don't recommend marijuana because:

  • It hasn't been approved by the Food and Drug Administration.
  • Marijuana smoke, like cigarette smoke, can harm your lungs.
  • Marijuana can harm your memory, judgment, and ability to process information. That can affect your ability to do things like driving a car or studying.
  • There are other legal drugs that may work just as well, such as new kinds of pain and nausea medicines.

Other medical experts sometimes do recommend marijuana because:

  • It can provide pain relief when normal pain medicines don't work or have unwanted side effects.
  • It can improve appetite and relieve nausea in people who have cancer or AIDS.

Be sure to let your doctor know if you are using medical marijuana. If you're pregnant, it's best to avoid alcohol and drugs, including marijuana.

How do you use medical marijuana?

Marijuana is usually smoked. It can also be brewed into tea, vaporized, applied to the skin, or eaten—usually mixed into food recipes.

Your mood, behavior, and ability to function may be affected for hours after you take marijuana. How quickly you feel the effects of marijuana—and how long the effects last—depends on:

  • How much you've taken.
  • How you've taken it.
  • The kind of marijuana you use.
  • How your own body is affected by it.

Side effects include dry mouth, nausea, vomiting, and red eyes.

Is it addictive?

Some people who regularly use marijuana become addicted. This means that they keep using marijuana even though it's having harmful effects on their lives.

If you've been using marijuana regularly and then quit, you may have withdrawal symptoms. These may include:


WebMD Medical Reference from Healthwise

Last Updated: November 15, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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