Getting high, but feeling low. Science is split on whether the effects of cannabis are good or bad, with recent research showing it could boost brain power in older adults, while other studies show ...

Canadian researchers at McMaster University studied marijuana users for a decade to find out its mental health impact ...

Researchers followed more than 400,000 teens until they were adults. It found that those who used marijuana were more likely to develop serious mental illness, as well as depression and anxiety.

LOS ANGELES - A recent study found that medical marijuana fails to improve symptoms of pain, anxiety and depression and effectively doubles the risk of developing addictive symptoms and cannabis use ...

Teens who use weed are twice as likely to develop psychotic or bipolar disorders, a new study says. They also are more likely to have depression and anxiety, researchers reported Feb. 20 in JAMA ...

An analysis of 35,000 Canadians shows that rising cannabis use and worsening mental-health symptoms are increasingly ...

In the first prospective study of synthetic cannabinoids or SCs - the group of chemicals that mimic the effects of marijuana - researchers have found that symptoms of depression, drinking alcohol, or ...