Medical Marijuana and Alzheimer's Patients

Written by Matt Berger
December 11, 2018

Minnesota becomes the latest state to allow medical marijuana for people with Alzheimer’s.

Some states are going ahead with plans to allow the use of marijuana by people with Alzheimer’s.

Health researchers say that might be risky — despite evidence there could be some benefits to certain people in some circumstances.

The problem with that evidence, they say, is that there just isn’t enough of it.

Last week, officials in Minnesota announced they would add Alzheimer’s disease to the list of conditions for which people can purchase medical marijuana.

If a resident has been diagnosed with Alzheimer’s, they would be allowed under state law to purchase medical marijuana from a licensed manufacturer starting August 1.

Alzheimer’s would join 13 other approved conditions, ranging from irritable bowel disease and intractable pain, to HIV and some cancers.

At least 13 other states already allow people with Alzheimer’s to use medical marijuana, according to the cannabis website Leafly.

Pennsylvania, one state that doesn’t allow it, approved a new way to speed up the addition of new conditions to its medical marijuana list last Tuesday.

Does marijuana help?

The expansion of access to marijuana for people with Alzheimer’s comes amid a lot of unknowns over the effects of pot on the symptoms and quality of life for people with the disease.

Researchers see the potential for benefits in some cases, but they issue an abundance of caution due to possible unforeseen risks.

Jan Malcolm, the Minnesota health commissioner, acknowledged as much in announcing the addition of Alzheimer’s to the approved list.

“Any policy decisions about cannabis are difficult due to the relative lack of published scientific evidence,” she said.

However, she pointed to evidence that medical marijuana can lead to improvements in patients’ mood, sleeping, and behavior as justification.

Alzheimer’s advocacy groups have acknowledged those benefits but noted the studies are limited so far.

“Symptoms such as agitation and aggression could in theory be counteracted by the effects of cannabis or its components,” according to the United Kingdom’s Alzheimer’s Society.

“However, scientific reviews have found that the trials and studies so far have generally been small or of low quality (see here and here for references), making it difficult to come to an informed conclusion.”

In a statement to Healthline, the Alzheimer’s Association in the United States said that “marijuana is, essentially, an untested drug in Alzheimer’s disease.”

“Its potential effectiveness and safety profile have not been thoroughly evaluated in clinical trials in people with (or at risk for) Alzheimer’s,” the organization added. “The Alzheimer’s Association believes that more research in this area is needed.”

Uncertainty makes decisions difficult

It seems the research is intriguing enough for some states to allow marijuana use for managing Alzheimer’s symptoms — in some cases, with prior doctor approval.

“I cannot imagine that it would be harmful at all, other than being a little freaky, as long as it’s used safely,” Gary Wenk, a behavioral neuroscience professor at The Ohio State University who has studied the influence of marijuana on Alzheimer’s, told Healthline.

“When high, they’d be more likely to get up and move around, but it could also increase their appetite, which could help. And a lot of older people have a lot of aches and pains — one thing marijuana is clearly good for is inflammation and pain,” he added.

Would he recommend someone with Alzheimer’s try it?

There are a lot of question marks, Wenk said, and those are complicated by the fact that, as an illegal drug under federal law, marijuana’s effects can’t be tested on humans.

“But what we know for certain is that it is not a treatment for Alzheimer’s. I wouldn’t recommend giving it at all,” he said.

Wenk has served on Ohio’s Governor’s Medical Marijuana Advisory Committee, which advises on such regulations in the state.

He said he gets a lot of emails from spouses or children of people with Alzheimer’s saying they’ve read marijuana could be good for their loved one.

“And I’m the one to blame for that,” Wenk said, citing an article he wrote in 2016 for Psychology Today. “But I don’t know how frightening it would be for someone to be demented and then be made high without their knowledge.”

Wenk does think marijuana can play a role in helping potential Alzheimer’s patients, though, which was his main point in that article.

He said some research has found smoking a small amount of pot — about one puff a day — for a long time after around age 40 may help prevent Alzheimer’s.

And he said there’s epidemiological evidence that those who smoked pot in the 1960s are not getting dementia at the same rate as those who didn’t. He’s trying to test that hypothesis on animals.

But there’s two issues with that: The pot we’re smoking now — bred and selected for certain traits over decades — is different from that of the 1960s.

And even if marijuana may play a role in preventing Alzheimer’s, that’s a whole other thing from treating it.

“By the time you’ve got it, it’s too late,” Wenk said.

Approving medical marijuana for people with Alzheimer’s, he added, “may involve as much myth and medicine.”

But it might result in more data to help support or refute those myths.

States gather data on what conditions medical marijuana was used for.

As of 2016, when Alzheimer’s was approved for use in 10 states, less than 0.5 percent of medical pot purchasers used it for Alzheimer’s. Some of those states also ask patients whether it helped.

The bottom line

Minnesota has joined at least 13 other states in allowing people with Alzheimer’s disease to access medical marijuana.

But health researchers say the evidence that pot could help with the symptoms and quality of life for such people is still limited.

One researcher says smoking small amounts of marijuana over a long period of time may help prevent Alzheimer’s.