Dr Peter Grinspoon, a primary care doctor, Harvard instructor and one of the leading clinical voices in the cannabis movement, on its medical, wellness and recreational benefits.
Most people who keep half an eye on the cannabis movement will have likely come across Dr Peter Grinspoon on Twitter. Among the chaos he is one credible voice, not afraid to call out misinformation.
But far beyond this, Grinspoon has been championing medical cannabis – quietly at first, and then not so – for his entire 25-year career.
His connection to the plant goes back even further. It was perhaps inevitable given that his father, Dr Lester Grinspoon, a long-standing associate professor of psychiatry at Harvard Medical School, was a pioneer best known for his groundbreaking works on the science and social policy of cannabis and psychedelics.
It was at just eight-years-old that Grinspoon saw the therapeutic potential of cannabis first-hand, during his brother Danny’s battle with leukemia.
“In the last year of his life when he was 16, my parents stumbled upon the idea of getting him medical cannabis for his nausea and vomiting,” he says.
“They bought it illegally – right when Richard Nixon was starting his war on cannabis – but it really helped him hold down food and feel better. I saw from a very early age that medical cannabis works for that indication and that it isn’t scary or bad.”
Thanks to his dad’s activism, Grinspoon was surrounded by cannabis advocates growing up, who he describes as some of “the most interesting and motivated”, academic scholars, lawyers and doctors, he’s ever met.
“There were always people in my house, not only discussing legalisation and the harms of the war on drugs, but also using cannabis,” he says.
“From an early age, I was immune to the propaganda that they give school about cannabis and amotivational syndrome. I saw these really motivated people every weekend in my house using cannabis.”
Grinspoon studied philosophy at a liberal arts college and went onto work for Greenpeace for five years before going into medicine. By the time he got to medical school it was a “culture shock”.
Dr Peter Grinspoon
“It was both culture shock and cognitive dissonance, because I had been pro or neutral cannabis, socially and intellectually my whole life,” he admits.
“But also, people drank a lot and fewer people used cannabis – it was weird socially to be at these parties with people getting drunk and yelling at each other.”
As a primary care physician at Massachusetts General Hospital, cannabis was always a part of his practice, and he was eventually able to prescribe it for his patients when it was legalised in the state in 2012.
“It’s been a part of my medical career since the beginning, because I’ve seen it work,” he says.
“It would be hard for me to not tell my patients who are going through chemotherapy that I think cannabis can alleviate some of their discomfort.”
Grinspoon played a role in helping secure both medical access and later, recreational legalisation in Massachusetts in 2016, going onto help prevent the banning of cannabis dispensaries in his own town.
On cannabis and medical burnout
Alongside practicing medicine, he is now a cannabis consultant, a board member of the advocacy group Doctors For Cannabis Regulation and a certified health and wellness coach, working with doctors and health professionals who are experiencing burnout.
His cannabis and coaching work is not unrelated. Having worked with many doctors struggling in the aftermath of the pandemic, Grinspoon is a firm believer that cannabis has a huge role to play in improving their wellbeing, despite it being “frowned upon” by medical boards, as it is still illegal under federal law.
“There are a lot of doctors that are suffering right now and I think that cannabis has a huge role to play in helping physicians,” says Grinspoon.
“Cannabis is therapeutic, it is something which helps people to relax, to be mindful, to sleep. It helps people with stress, and helps alleviate the PTSD symptoms that doctors are starting to develop in response to the trauma of being a doctor.”
He continues: “Our medical boards which regulate doctors in different states are hysterical about cannabis…they’re slowly starting to change but generally speaking they still believe a lot of the old nonsense.
“Doctors should have the choice. A lot of people rely on a substance. The only choice has been alcohol for the last 80 years because of prohibition, so now it’s a little bit confusing that the medical boards and regulators don’t encourage [doctors] to use a safer choice. It’s a very backwards policy, transitioning from alcohol to cannabis would have a huge harm reduction benefit.”
On the opioid crisis
He also believes that cannabis has a role to play in tackling America’s opioid crisis. Data from the CDC’s National Center for Health Statistics, indicates that there were more than 100,000 deaths from opioid overdose in the US in the year ending April 2021, a 25 per cent increase from the year before.
Grinspoon says cannabis can be used to mitigate this in a number of ways.
He explains: “With a new patient who has chronic pain, you can start them on cannabis instead of opiates, so you have less people on opiates and less opioid addiction. It can also be offered to patients who are on chronic, high doses of opiates to taper them off. Opiates and cannabis work on the same receptors, so you can lower the dose of opiates if you can use cannabis [in conjunction with].
“Cannabis is also an incredibly effective treatment for many of the withdrawal symptoms from opiate addiction and there’s no evidence that people using cannabis for withdrawal do any worse than using pharmaceuticals.”
He adds: “The fifth way of using cannabis is as an opiate substitution treatment, like methadone or buprenorphine. I know people that have used it for that purpose, but we don’t have enough evidence.”
As someone who has overcome addiction himself – Grinspoon wrote a memoir confronting his own problematic relationship with prescription medication – he can personally vouch for its benefits.
“I have found it helpful with withdrawal symptoms,” he admits.
“You could ask anybody who’s gotten off heroin or prescription pills, that cannabis is incredibly effective, way better than the stuff they give us.”
He continues: “In the past, I’ve used it to treat migraines and chronic pain. There are also a lot of wellness benefits to that doctors never talk about. I feel like a lot of the most important insights that I have had in my life have been engendered by the use of cannabis. It really does give you insight into your role in the universe in a way that nothing else does.”
On the role of GPs in prescribing
Despite his numerous speaking and writing hats, it’s important to Grinspoon to keep his hand in with frontline prescribing.
While in the UK only specialist consultants are allowed to prescribe cannabis, in his experience, primary care doctors are much better placed to do so.
“It’s an extra tool that makes my life easier,” he says.
“I incorporate it as an option when I treat chronic pain, anxiety, insomnia and things that are very difficult to treat like irritable bowel syndrome, colitis, fibromyalgia, or PTSD.
“You see a lot of different things in as a general doctor and it gives you a lot of opportunities to use cannabis with patients.”
He continues: “The fact that GPs can’t prescribe or certify cannabis makes no sense.
“The general doctors know the patient, they know what other drugs that patient is on, they know if you’re going to have surgery and the anaesthesiologist needs to know about it, and they communicate with the specialist. Not only should general doctors be allowed to prescribe cannabis, I think that should be the basis of where cannabis comes from.
“The UK has it absolutely backwards. It sounds cynical, but it’s like one of the arbitrary roadblocks they put up to slow down medical cannabis, as opposed to anything based on science, public health or common sense.”
On the value of real-world evidence
Randomised control trials are seen as the gold standard in scientific research. But when it comes to cannabis, which contains a variety of different cannabinoids and terpenes, experts in the field know that it’s the real-world evidence which holds the key to unlocking its true potential.
But how do we convince the wider scientific community?
“There needs to be a broader definition of evidence,” says Grinspoon.
“Cannabis does a lot of things at once. If someone has fibromyalgia it can help with their pain, anxiety, fatigue, sleep, their general discomfort and misery. It almost always improves quality of life for the majority of patients and its hard to capture that in a randomised control trial.
“It’s also a question of evaluating the ‘evidence’ that we already have, and understanding that the US government funded most of it and had their finger on the anti-cannabis side of things. It was prohibited to look for benefits, it just wasn’t funded and it was encouraged to look for harms. That’s not objective science.”
As an aside, he adds: “It’s weird how those who don’t treat people with cannabis, think they know what it works for and what it doesn’t work for.
“The whole point of real-world evidence is that it is listening to those who do treat people with cannabis. We have a lot more experience, and we’re not basing this on selectively curated studies.”
On recreational vs medical cannabis
Grinspoon is unusual in the medical community in that he openly speaks about the benefits of both medical and recreational cannabis use. But he’s clear on the fact that there is a difference between the two.
“There’s a fine line between recreational and medical, but I don’t agree that all use is medical use,” he says.
“If I have a vape pen and smoke it with my friends before a concert, so the concert is more fun, that is recreational. When my brother Danny was dying of cancer, he was using it medically.”
He continues: “A lot of use is in the grey zone, to help with creativity, relaxation, connection, sexuality, and spirituality. The wellness benefits of cannabis and the lifestyle enhancements have been documented for thousands of years.
“If you use cannabis from a dispensary in the US, you could use it for fun and you could use it if you have back spasms. There is a huge overlap and most use – not all but most – is probably somewhere in a continuum, rather than a binary definition.”
On the endocannbinoid system not being taught in medical schools
Another impact of prohibition, alongside the fact it wasn’t discovered until the early 90s, is that the endocannabinoid system (ECS) – the neurotransmitter system responsible for rebalancing the human body – is not commonly taught in medical schools.
According to Grinspoon, only around 13 per cent of medical schools in the US teach doctors about the ECS.
“Patients have the right to expect doctors to know something about this neurotransmitter system that is integral to all the other neurotransmitter systems, and to have some facility with cannabis so that they can sensibly answer questions,” he says.
“If doctors don’t know – or people are too afraid to talk about cannabis with their doctor – they will go to other sources of information, such as budtenders who are not qualified to give medical advice.”
On the future of cannabis in medicine
So where does cannabis fit in the future of healthcare?
“It depends what else we discover,” says Grinspoon.
“Now that people are actually studying the ECS, hopefully we’re going to discover all kinds of things that can help people. As we develop more medications and eventually start teaching and continuing to study the ECS, both natural cannabinoids and different synthetic cannabinoids are going to become a greater part of medicine.”
He adds: “I think we will discover that some of the diseases we are generally very bad at treating are because they’re mediated by the ECS.”
Find out more about Dr Grinspoon’s work here and follow him on Twitter @Peter_Grinspoon
Home » Advocacy » “I saw from an early age that it works” – Dr Peter Grinspoon on the therapeutic potential of cannabis