Marijuana Use in Teens: Care Instructions

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The two most active chemicals in marijuana are THC and CBD. THC affects how you think, act, and feel. It can make you feel very happy or "high." CBD can help you feel relaxed without the "high." Marijuana products usually contain both THC and CBD.

THC usually can be found in urine for a few days after marijuana is used. If you regularly use a lot of marijuana, THC may be found for weeks after use has stopped.

There are many types, or strains, of marijuana. Each strain has specific THC-to-CBD ratios. Because of this, some strains have different kinds of effects than others. For example, if a strain of marijuana has a higher ratio of THC to CBD, it's more likely to affect your judgment, coordination, and decision making.

In the United States, it's against federal law to possess, sell, give away, or grow marijuana for any purpose. But many states allow people with certain health problems to buy or grow it for their own use. And some states allow people over age 21 to use it for recreational reasons. Medical marijuana may be prescribed for teens with certain medical conditions. But recreational marijuana by teens is illegal everywhere in the United States.

Many schools and employers have strict rules about drug use. A positive drug test might cause you to be expelled from school or keep you from getting into a school you want to attend. You might not be able to take part in school sports or clubs. Or it might cause you to lose a job or keep you from getting hired.

If you use marijuana, take steps to lower your risk.

Follow-up care is a key part of your teen's treatment and safety. Be sure to make and go to all appointments, and call your doctor if your teen is having problems. It's also a good idea to know your teen's test results and keep a list of the medicines your teen takes.

How can you care for yourself at home?

  • To have the lowest risk, don't use marijuana. But if you do use it, limit your use.
  • Know what you're using. Choose products that have low levels of THC. The type (or strain), strength, and effects of marijuana can vary greatly. And understand that how soon you may feel the effects of the product you use and how long those effects may last can vary. It depends on how you take it.
  • Don't drive or operate machinery after you use marijuana. Using marijuana may affect your judgment, coordination, and decision making.
  • Don't smoke marijuana. The smoke can damage your lungs.
  • Don't use marijuana with alcohol, tobacco, or illegal drugs.
  • Don't use synthetic marijuana, such as K2 and Spice. They can have very bad side effects.
  • Reduce the risk of medicine interactions. Marijuana can be dangerous if you take it with blood thinners or with medicines that make you sleepy, control your mood, or lower your blood pressure.
  • Keep others safe. Store marijuana in a safe and secure place. This is especially important with edible marijuana, which can be easily mistaken for treats or snacks. Make sure that children, friends, family, and pets can't get to it. And protect others from secondhand smoke.

When should you call for help?

Call your doctor now or seek immediate medical care if:

  • You have new or worse symptoms of cannabis hyperemesis syndrome (CHS), such as:
    • Vomiting that doesn't stop.
    • Not being able to keep down fluids.
    • Belly pain.
    • Symptoms that go away briefly when you take a hot bath or shower. This is one of the signs of CHS.
  • You have symptoms of dehydration, such as:
    • Dry eyes and a dry mouth.
    • Passing only a little urine.
    • Feeling thirstier than usual.

Watch closely for changes in your health, and contact your doctor if:

  • You think you have a problem with marijuana use.

Where can you learn more?

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The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.