The marijuana plant has chemicals that may help symptoms for some health problems. More and more states are making it legal to use the plant as medicine for certain conditions. But there isn’t enough research to show that the whole plant works to treat or cure these conditions. Also, the government still doesn't think of marijuana as medicine, so it's still illegal at the national level.
Two medicines have been made as pills from a chemical that's like the one in the marijuana plant that makes people feel "high." They can treat nausea if you have cancer and make you hungry if you have AIDS and don’t feel like eating. But this chemical affects the brain, so it can do things to your body other than just working as medicine. One brain effect is that over time, marijuana chemicals can lower how smart someone is (called IQ). This brain effect could be permanent if you start using marijuana a lot as a teen.
Another marijuana chemical that scientists are studying doesn't make you high. Scientists think this chemical might help kids who have a lot of seizures (when your body starts twitching and jerking uncontrollably). Some studies have started to see if it can help.
Because marijuana is often smoked, it can hurt your lungs. These and other effects on the brain and body could make marijuana medicine more harmful than helpful. Another problem with marijuana as a medicine is that the ingredients aren't exactly the same from plant to plant. There's no way to know what kind and how much of a chemical you're getting.
Scientists are trying to find ways to make safe medicines from marijuana.