By ABIGAIL ZUGER, M.D.

Two-legged or four-legged, some guinea pigs have more fun than others.

Among the human variety, Dr. John Clendinning and Dr. David Casarett might be considered particularly fortunate. Back in 1843 Dr. Clendinning, a London physician and bad insomniac, reported on his personal experiences with various sleep-inducing substances. The clear winner was a tincture of marijuana, which brought him a good night’s sleep with none of what he termed opium’s “inconveniences.”

What Is Medical Marijuana?

Medical marijuana is any part of the marijuana plant that you use to treat health problems. People use it to get relief from their symptoms, not to try to get high.

Most marijuana that's sold legally as medicine has the same ingredients as the kind that people use for pleasure. But some medical marijuana is specially grown to have less of the chemicals that cause feelings of euphoria.

We parked the car at a train tracks. It had been a 25-minute drive from Portland, maybe more. My friend and I got out and stretched our legs. The train was going by and we couldn’t see anything.

“Is this the place?” I asked.

“I don’t know,” he said. He was local but hadn’t been out this way before. “I think there’s water down there. Maybe it’s on a houseboat.”

Several other people joined us at the train tracks, approaching warily and steadily, like deer at dusk.

“Are you here for the pot party?” one of them said, as though they couldn’t believe it was possible that such a thing existed.

Teenagers have discovered a new way to inhale marijuana — e-cigarette vaporizers, according to a study released Monday.

About 27% of high school students who have used both marijuana and e-cigarettes reported using the devices to vaporize cannabis. Those most likely to vaporize pot with e-cigarettes included males and younger students.

E-cigarettes are designed to vaporize solutions containing nicotine, said co-author Meghan Rabbitt Morean. But, she noted, “teenagers are resourceful, and it was only a matter of time.”

Vaporizers give kids a better way to hide what they're inhaling.

Colorado has brought in more than $150 million in marijuana tax revenue, according to official state data.

That doesn't make it a budgetary panacea, warn lawmakers. 

"The big lesson we tell other states is you probably shouldn't legalize marijuana if you want to make money – that's not why you do it," said J. Skyler McKinley, deputy director of the governor's Office of Marijuana Coordination, to the Huffington Post. "You do it because you think that a regulated marketplace might be safer than an unregulated marketplace, or you believe that the war on drugs didn't work."

Bob and Cathy Jordan say her ALS is relieved by medical marijuana, and are supporters of legalizing it in Florida.(Photo: WTSP)

PARRISH, Fla. -- When you pull up to the home of Bob and Cathy Jordan and see a FLCAN sign, you know exactly what they stand for.

"We're flat out legalization but regulate," said Bob.

Cathy has Lou Gehrig's disease or ALS. It's deadly and there's no known cure. But, she is a 30-year survivor of it. The married couple of 33 years attributes that to marijuana.

"It's a horrible disease, I think it's the worst disease out there," Bob said.

"She goes 10 days without cannabis, at the most 10 days, her twitching comes back, she starts drooling."

We've told you before about marijuana's effect on lungs, bones, cancer cells, breast cancer, metabolism, and sex drive.

Bernie Sanders has increased his lead on Hillary Clinton in New Hampshire according to the latest NBC/Marist poll. The progressive insurgent candidate that many cannabis law reform advocates have rallied around, has been the target of criticism from Clinton surrogates in recent day. Sanders responded that Clinton’s campaign must be “nervous” if they are taking shots at him.

Few issues have garnered more attention from Americans in recent memory than the expansion of marijuana.

Marijuana's tug-of-war

Just a decade ago, based on a poll from Gallup, only around a third of respondents to its survey were in favor of seeing marijuana legalized on a national level. Yet, here were stand in 2015 with three major polls (Gallup, General Social Survey and Pew Research Center) all pointing to a majority of respondents being in favor of marijuana's nationwide legalization, at least by a slim margin. Focus solely on medical marijuana and the responses swing even more strongly into the "favorable" camp.

At least 67 people are in prison right now, sentenced to die there for selling marijuana, according to the best available data. Until last week, Jeff Mizanskey was one of them. 

“Man, I feel great,” the great-grandfather told MSNBC, as he contemplated his first weekend as a free man in more than 20 years. His sentence was commuted in May from life without parole to simple life, and on Tuesday he walked out of a maximum security Missouri prison.

Someone helped him dial this wondrous new thing called a smart phone. “Do you have children?” he asked. “The day a child is born – that’s what this feels like for me. I’ve finally made it to freedom.”