The U.S. policy debate is largely centered on the question of whether more research is needed on potential benefits and harms — particularly around potency — since the market is awash in so many different products. The vast majority of states have approved some form of marijuana for medicinal purposes.
“There are so many indications for which the dispensaries are selling marijuana, and yet the evidence for most of them is basically non-existent,” said National Institute on Drug Abuse Director Nora Volkow, citing cancer, post-traumatic stress disorder and attention deficit disorder.
There is some evidence marijuana can help with problems like chronic pain, loss of appetite and symptoms of dementia, she added. There are now also Food and Drug Administration-approved drugs using cannabis compounds.
But the way people consume the plant, such as smoking, can have negative effects too. Volkow also cited concerns around psychosis and impacts on brain development.
NIDA has been following nearly 12,000 children in an ongoing study since 2015, when the children were 9 or 10. Those kids are now 15, around the age when many marijuana users first start. The agency is also launching a medical marijuana registry to track how patients use the drug.