A recent study found that medical marijuana failed to quell symptoms of anxiety and depression and instead doubled down on risks for developing addictive symptoms and cannabis use disorders.
And while marijuana has been shown to help ease pain and a few other health problems, two-thirds of U.S. states have decided pot should be legal to treat many other conditions with little scientific backing.
"In this first study of patients randomized to obtain medical marijuana cards, we learned there can be negative consequences to using cannabis for medical purposes. People with pain, anxiety or depression symptoms failed to report any improvements, though those with insomnia experienced improved sleep," Gilman added.
The U.S. government, meanwhile, both considers marijuana an illegal drug and a therapeutic herb worth more study.Besides chronic pain, there’s strong evidence marijuana or its ingredients can ease nausea and vomiting from chemotherapy and help with symptoms of multiple sclerosis. British drugmaker GW Pharmaceuticals is seeking U.S. approval for Sativex. Other companies are pursuing Food and Drug Administration backing for products based on marijuana ingredients.