Inhaling secondhand marijuana smoke even for just 1 minute may temporarily affect how blood vessels function, according to a new study done in rats.
Marijuana is an age-old drug made from parts of the Cannabis plant. It contains the mind-altering chemical tetrahydrocannabinol, or THC. Several countries, and a number of U.S. states, have legalized the drug for medical or recreational purposes. Here's the latest news on marijuana, from how it affects the brain and body, to its potential medical benefits or harms, to possible impacts of legalization.
The number of young kids in Colorado who accidentally consume marijuana has increased since buying the drug for recreational use became legal there in 2014, according to a new study.
Exactly how much marijuana is in a typical joint may be less than previously thought, a new study finds.
Users of increasingly popular street drugs called synthetic cannabinoids are showing some incredibly strange behaviors.
With brain-scanning and longer-term studies, researchers are learning more and more about the effects marijuana may have on the brain.
People who use marijuana for many years may lose their brain's "natural" responses to rewards, a new study suggests.
"Cannavaping" — using e-cigarettes for vaping cannabis — may be a better way to use medical marijuana, according to a small, early study.
After Washington legalized recreational marijuana, the percent of drivers involved in fatal crashes with THC in their blood doubled, research suggests.
The question of whether using pot lowers IQ is still contested, but several long-term studies find no significant cognitive declines.
A new review points to promising research on marijuana as a cancer treatment, but questions remain about the usefulness of the drug for human patients.
People with psychiatric disorders who also use marijuana may spend more time in the hospital for their conditions, a new study from England suggests.