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Drug Facts Chat Day: Marijuana

Marijuana and mental illness

NIDA-funded research shows that when use starts during the teen years, marijuana is associated with impaired thinking, memory, and learning functions. It is also associated with a number of mental conditions, including psychosis (schizophrenia), depression, anxiety, substance use disorders, and suicidal thoughts or attempts. However, it is not yet clear if marijuana directly causes these issues or just makes them worse. Currently, there is strong evidence for the link between marijuana and psychosis in persons with a preexisting genetic or other vulnerability. Recent research also suggests that smoking high-potency marijuana every day could increase the chances of developing psychosis by nearly five times compared to people who have never used marijuana.  Marijuana may contribute to the development or worsening of the mental illness, or it may reflect combinations of the above.

Marijuana MTF results

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Is marijuana a gateway drug?

The gateway concept is one that generates a lot of controversy. The research is not yet settled but it suggests that while most people who smoke marijuana do not go on to use other drugs, most teens who use other illegal drugs try marijuana first. For example, the risk of using cocaine is much greater for those who have tried marijuana than for those who have never tried it. However, this is also true for alcohol and tobacco. Animal studies suggest that—because the teen brain is still developing—early use of marijuana alcohol or tobacco may alter the brain’s reward system, putting teens at higher risk of using other drugs. In addition, using marijuana puts children and teens in contact with people who use and sell other drugs, increasing the risk of additional drug use.

Why is weed illegal if it is a medicine?

Marijuana for medical use has been in the news a lot lately, but the marijuana plant has not been approved by the FDA as a medical treatment. Some research suggests that certain active ingredients in marijuana, like THC and cannabidiol (CBD) might help with things like epilepsy, or pain. Some states allow doctors to recommend marijuana for adults with certain conditions, but it should be carefully discussed with a medical professional. People who sell medical marijuana at legal dispensaries are not usually medically trained.

Scientists are studying ingredients in marijuana to try to develop new medications. A pill form is already available for some conditions, such as nausea from cancer chemotherapy and weight loss in patients with AIDS. A CBD-based liquid has been approved to treat severe childhood epilepsy. However, smoked marijuana is unlikely to be an ideal medication because of its negative health effects.