CBS rejected a Super Bowl ad that makes a case for medical marijuana. Acreage Holdings, which is in the cannabis cultivation, processing and dispensing business, said it produced a 60-second ad that shows three people suffering from varying health issues who say their lives were made better by use of medical marijuana. Acreage said its ad agency sent storyboards for the ad to the network and received a return email that said: “CBS will not be accepting any ads for medical marijuana at this time.”

New neuroimaging research provides new insight into how tetrahydrocannabinol, or THC, the main psychoactive compound in cannabis, affects the human brain. The study found that THC increases glutamate concentrations in the striatum, a major brain structure involved in the coordination of body movement, decision-making and the initiation of action.

The figure doubled from the year before.

As more states legalize cannabis consumption, many more people will likely use medical marijuana as a supplement to or substitution for prescription drugs, says a University of Michigan researcher. A new study by Daniel Kruger of the U-M Institute for Social Research found that 44 percent of medical cannabis users stopped taking a pharmaceutical drug, or used less of one, or both, in favor of cannabis.

A few years ago, I went to a new physician for a checkup. She ran through the list of questions that doctors like to ask...

Buried deep inside a mountain on a remote Norwegian island, agricultural institutions from around the globe are collaborating to safeguard important crops in the event of global catastrophe. That includes marijuana. Currently, there are over 29,500 marijuana seeds – including 31 strains of marijuana and 8 strains of hemp being held in the vault. That is more seeds than there are asparagus, blueberry or raspberry seeds stored at the facility.

More than half of people who take medical cannabis for chronic pain say they’ve driven under the influence of cannabis within two hours of using it, at least once in the last six months, according to a new study. One in five of them said they’d driven while ‘very high’ in the past six months, researchers from the University of Michigan Addiction Center report in the journal Drug & Alcohol Dependence .

In a small study of infrequent cannabis users, Johns Hopkins Medicine researchers have shown that, compared with smoking cannabis, vaping it increased the rate of short-term anxiety, paranoia, memory loss and distraction when doses were the same.

Permitting pot is one thing; promoting its use is another.

Thailand has become the first Asian country to legalize medicinal marijuana after parliament voted to amend a narcotics law. The country had a tradition of using marijuana to relieve pain and fatigue until the 1930s.

This week, a plant that's nearly identical to marijuana is set to become legal to grow in the US. Thanks to the US Farm Bill, which the House passed on Wednesday in a 369 to 47 vote, American farmers will be able to plant and harvest hemp, a strain of the same plant species from which marijuana originates. The bill passed the Senate Tuesday in an 87 to 13 vote, and President Donald Trump has indicated his support. Hemp legalization has been a longtime goal of Senate Majority Leader Mitch McConnell, a Republican from Kentucky, who believes it can help replace tobacco as a key crop for his state's farmers.

Legislation comes ahead of a referendum on recreational marijuana use in next two years

Millions of Canadians use it. Here's what happens to your brain when you take a hit.

Stretching the day for tiny marijuana plants at a Lafayette greenhouse long after night falls makes for a hefty electric bill. Even with big investments in a computer system to control heat, light and humidity, and in more-efficient light bulbs and fans, RiNo Supply Co. general manager Brian Matthews says 85 percent of the energy costs at the greenhouse are in lighting.

How can vaping be a gateway drug if drug usage is down amid a vaping "epidemic" among the youth?

A moss-like plant grown only in a few countries may offer better pain relief than medical marijuana, animal research suggests.

When researchers convinced a group of young people to stop smoking pot, their cognition quickly improved. This adds to research warning against teen pot use, despite marijuana's growing acceptance.

The first Food and Drug Administration-approved drug containing an ingredient derived from the marijuana plant went on sale Thursday in the United States.

A substance that gives pot its kick appears to reduce the brain changes associated with Alzheimer's disease – at least in mice. In mice that had been genetically tweaked to develop symptoms like those of Alzheimer's, animals that received a synthetic form of tetrahydrocannabinol for six weeks performed as well as healthy mice on a memory test, scientists reported Tuesday at the Society for Neuroscience meeting in San Diego.

Rampant overproduction in Oregon’s market for legal, recreational marijuana has produced a 50 percent decline in prices, according to state economists. That widely documented collapse has been hard on farmers and retailers – but a boon for consumers. A new state analysis finds the price collapse sparked a big uptick in marijuana purchases – and a corresponding increase in associated tax revenue.

In the latest issue of Genome Research, a group of North American scientists have, for the first time ever, published a full map of the cannabis genome. Among the myriad of interesting insights to glean from the chart is the finding that the genes that encode for THC and CBD production evolved thanks to bits of DNA introduced by viruses that infected the plant and successfully colonized its genome millions of years ago.

On Monday, the first business day after Utah’s medical cannabis initiative became law, state legislators supplanted it with a more tightly controlled plan for providing marijuana-based treatment. The Utah Medical Cannabis Act, designed as a replacement for voter-approved Proposition 2, breezed through the Utah House of Representatives and Senate during Monday’s special session. The one-day gathering of state lawmakers has been in the works since October, when Gov. Gary Herbert announced that supporters and opponents of Prop 2 had reached consensus around a legislative solution to their disagreements.

Around the world attitudes towards the use of cannabis are shifting. Mexico's new government plans to legalise recreational cannabis use, as does the incoming government of Luxembourg. Meanwhile, New Zealand's leaders are considering a referendum on what their approach should be. As public opinion - and that of governments - changes, it seems increasingly likely that other countries will follow, raising questions about how they work together to manage the use and supply of cannabis.

Grinning from ear to ear with his endearing gappy smile as Santa hands him a present, Alfie Dingley is thrilled to bits. Like most children, the seven-year-old has been looking forward to meeting Father Christmas. But, unlike most youngsters his age, Alfie has only just un­­der­stood who Santa is. So, for the first time since he was born with a rare form of epilepsy – and thanks to a landmark drugs ruling – his family can at last celebrate the festive season properly.

Marijuana may not be as damaging to the brain as previously thought, according to new research from the University of Colorado Boulder and the CU Change Lab.

Two new studies support this correlation

The Trump administration is abandoning a Justice Department plan to crack down on recreational marijuana in states where it is legal, a move that enables cannabis businesses in California and several other states to operate without fear of federal raids or prosecution.

The City of Seattle on Friday filed a motion asking the court to vacate hundreds of marijuana possession convictions going back three decades and adversely impacting people of color.

As Canada prepares to legalize marijuana this summer, politicians are facing growing calls to grant a blanket amnesty for people convicted under the existing drug laws – many of whom belong to marginalized groups. Since the prime minister, Justin Trudeau, was elected in 2015 on a manifesto promise to legalize cannabis, more than 15,000 people have been charged over marijuana-related offences – joining close to 500,000 Canadians with marijuana charges on their criminal record.

This year’s Canadian Brewing Awards are being held in Halifax, and brewers from across the country are showing off their finest beers. But much of the discussion at this year’s conference surrounds a beer that doesn’t actually exist yet.

An active compound in marijuana called tetrahydrocannabinol (THC) has been found to promote the removal of toxic clumps of amyloid beta protein in the brain, which are thought to kickstart the progression of Alzheimer's disease.

When Canopy Growth opened its first cannabis factory in an old chocolate plant near Ottawa four years ago, it did so predicting a bright future. Canada had already legalized medical marijuana, and Canopy predicted full legalization for recreational use to be next. What the company hadn’t predicted, however, was the sudden flood of foreign visitors. Politicians and police authorities from Jamaica, Germany, Denmark, the Netherlands, Greece and Australia have all come knocking, as well as doctors from New Zealand, Brazil and Chile, along with groups of corporate investors and bankers...

The Senate voted 52-29 to approve the government's newest version of Bill C-45 on Tuesday evening.

Margaret Thatcher’s favourite free-market thinktank has called on the government to legalise cannabis, arguing that the move could generate more than £1bn in extra tax revenues every year, as well as savings in health and other public services. Britain’s black market in cannabis is worth £2.6bn annually, with 255 tonnes sold to more than 3 million people last year, according to the Institute of Economic Affairs (IEA).

Medical marijuana laws by state. Includes fees, possession limits, and other medical marijuana program guidelines.