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Medical marijuana

April 10, 2020

About the Author

photo of Peter Grinspoon, MD

Peter Grinspoon, MD, Contributor

Dr. Peter Grinspoon is a primary care physician, educator, and cannabis specialist at Massachusetts General Hospital; an instructor at Harvard Medical School; and a certified health and wellness coach. He is the author of the forthcoming book Seeing … See Full Bio
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Brian Harrison
March 13, 2018

Very interesting post, may be worth noting that there is no real need for the THC element within the medical products, studies have shown that THC and CBD combined at a 1:1 ratio is beneficial towards pain, however it has also been discovered that THC can modify our brains functions, making it hard for some people to continue with specific jobs.

Cbd Has been discovered to be effective for pain without the use of THC, this is one of many reasons why it hit the world market with a storm, it allowed a person to relieve themselfs (at a financial cost) from pain but without the psychedelic side effects of the THC.

There is a big study happening in the UK at the moment, its still relatively new but its full supported by a big company the CBD Medical and Health Research is a very good read also, based on real human subjects.

The study linked above shows that THC is not needed for the effects that people look for when using CBD, it is THC that is truly illegal in most places around the world, and it is THC that is used to get a high, remove this element and the drug is far less likely to be abused, CBD is also known for helping with drug addictions and hold zero addictive properties.

March 14, 2018

Love this article and the best part is the author giving his peers advice to keep an open mind and to educate themselves so they can talk with their patients and assist them. Brian, I encourage you to keep an open mind. Your response portrays a person bias towards cannabis. I encourage you to open your mind and so your research. Check out The Sacred Plant Docuseries. Also would you mind supplying links to back your comments on THC having no benefits as well as any resource or scientific study that shows CBD can supply the same benefits as THC. As a user and advocate of the Sacred Plant, I can share the health benefits from my own personal use. My husband just got diagnosed with Colon cancer when this blog was posted. We are eternally grateful to have access to Cannabis and the knowledge in making his medicine. Thank God for Rick Simpson and his oil discovery. I also look to history as our best and wisest teacher. Do you khow long Cannabis has provided medical relief benefits to millions of humans suffering. Finally, as a believer in God knowing He created hemp and cannabis and made both for our benefit, I look forward to the much needed studies that man prevented. Man made it bad and now that millions are dying of disease man is rethinking his actions. Hemp with its CBDs is amazing but so is Cannabis with its THC. THC does alter our thinking and for the better. Did you know cannabis consumption causes neurogenesis in adults? Did you know people have cured cancer ingesting Cannabis oil? Do you know all the ailments cannabis treats? Do you have any friends who have benefited from cannabis? Is the CBD oil explosion a health trend or fad? How many companies will make billions selling fake CBD oil because of this fad or trend? Some questions to ponder since the media controls the marketplace.

Doug Rice, President, Epilepsy Assn of Utah
March 14, 2018

The points regarding no need for THC are not entirely accurate. Our daughter had great results using CBD oil to reduce epileptic seizures. But we saw total control by adding small doses of THC.
There are methods available to minimize the issue of impairment with cannabis. THCa, the raw component in the plant, does not get a patient high. THC needs to be decarboxylated (usually by applying heat over 180F) before it becomes psychoactive. CBD also attenuates the effect of THC, so some of the psychoactivity is subdued by having the combination of CBD and THC.

March 12, 2018

A new powerful report published by the American National Academies of Sciences has examined the amount of research that has been published for years on the use of cannabis for medical or recreational purposes, establishing for the first time with a certain claritywhat are the positive and negative effects on proven health.

March 7, 2018

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Audrey Domreis
March 1, 2018

i really enjoyed this article. I am 17 and have been using medical for about 2 years (not smoking, just oil and making smoothies with the sun leaves) and refuse to take prescription medication from the hospital, it has helped a LOT with my anxiety and depression, i cant even explain how much. it has also helped with my joint pain and helps me sleep. Two years ago my grandmother was diagnosed with a glioblastoma the size of a baseball, she started using the oil and started juicing to help shrink the tumor. She started that and completely changed her diet, last year around August the doctor couldn’t find the tumor anymore and it was great, she could finally talk and text and write and remember things. Although this year as soon as she stopped, the cancer came right back and she is in the hospital again now. Before this I had a pet rat and didn’t realize she could get stomach cancer from feeding her corn, i put her on a different diet and constantly made cannabis salve and oil for her. I ran out of it for a week at some point though and the cancer came back within a day and had killed her 🙁
This amazing plant has over 20,000 uses and i would Love to study it one day more than i already do on my own. i hope people educate themselves on this topic more and actually understand what it can do, because before it became illegal we had used it for thousands of years. it really is an amazing plant.

February 26, 2018

Hi Dr. Grinspoon,

I am really confused about this study. I read lots of article which it says Marijuana have bad effect on brain in long term and some article says opposite. Doesn’t it effect on lungs like when you smoke cigarette as well? does it make you addicted?
Could you introduce a reliable website I can read about Marijuana more?
Thank you!

Peter Grinspoon, MD
February 27, 2018

Try this, it’s long but excellent, from National Academy of Sciences:

Neva Morgan
February 26, 2018

Hi Peter. My husband has been taking Xarelto AND Pletal (as prescribed by a doctor despite pharmacists filling the prescriptions with a bit of shock and stating they should not be taken together) since he had a DVT in his thigh. This happened after knee surgery in Jan 2013, flying 13 hours in March 2013 totally unaware or warned by our doc that this was dangerous after surgery. The DVT in the back of his thigh threw a large clot and put him in ICU on life support in the Philippines, with a Pulmonary Embolism. He was inches from death for approx 6 days and then 10 days induced coma total in ICU, 1 month in hospital recovering (thankfully) learning to walk again etc. Since then he has been on 10mg Xarelto (night dose) and 100mg Pletal (morning dose) and we have been too terrified to reduce the dose in any way even though the docs in Philippines said continue life long Xeralto and then wean off Pletal after 3 months, because the doc in Spain when we came back here said, leave it as it is. Its now nearly 5 years later and he’s still on both drugs. Approx 7 months ago he and I started taking 3 micro doses of THC FECO per day, mainly as a cancer preventative. Since then my husband and I have both lost weight. Ive lost over 40lbs and still losing as I was obese and am still overweight but its just naturally slowly coming off. (so unexpected, but good side effect) My husband 6’2″ was never overweight, in fact he has always been fit and muscular, and he has lost approx 20lbs which on his frame makes him look like he’s been locked up somewhere and starved, but it appears to be muscle mass, its definitely muscle mass and despite working out and being a very fit active man (68 yrs and fitter than most 30 somethings) his muscle loss is not changing, he has managed to put on just 2lbs (also taking ISO Protein but no idea if thats helping or not). We are wondering if it is the cannabis’ blood thinning capabilities, in addition to the thinning meds he is on that is causing muscle loss and if as a result we could finally wean off some of the chemical thinners if only by a percentage, or maybe remove one completely and keep the other while maintaining the FCO which we plan to take in tiny maintenance doses for the rest of our lives. We are in Spain and the docs here seem to refuse to “decide” re the blood thinners, they almost cover their eyes when we ask the question “philippine docs said to wean off Pletal.. you have done new tests.. do we wean of Pletal? They will not respond! While its legal here to use medical cannabis, the lack of knowledge by doctors here including a Dutch doctor, make it difficult to consult on the interaction and the possibility of what we desire, which is to cut down on his Xarelto and Pletal, even if its just incremental, i.e. trimming 20% off each pill. We plan on seeing our doc tomorrow for the first time since starting on the FECO for blood tests to find out if his blood is now possibly “too thin” which in a way would be good as it would be a sign we could reduce one or both of the chemical blood thinners while maintaining the cannabis dose and then get him tested monthly as he weans off under doc supervision. This is our hope, but we are on our own as far as knowledge of the two sides i.e. cannabis/western medicine, and we are aware that we will have to make a decision on our own after the blood test results. If we find out his blood is “thin” then I imagine the cod might suggest a dose reduction but he has been loath to change anything in the past. It will be we who decide IF to wean, which drug to wean off, or a bit of both, or all of one .. this is terrifying, but thats how it is.
So finally to my question
Whats the question? I’m not sure??
If his blood work comes back that all is ok re blood texture clotting etc, then weaning off is bad? Why the muscle loss? Is there any data ANYWHERE that suggests either Xarelto or Pletal affect muscle mass over the long term? (5 years) It would seem possible that over thin blood would affect muscles but what do I know? He has also experienced some dizziness (light headed) this last year which again, timing wise, ties into the addition of FECO to his diet but Im not blaming the FECO, Im hoping the FECO is acting as a blood thinner and that we can reduce the Chem meds which according to studies Ive read with tears streaming down my face, have multiple side effects.
Our desire, aim, hope, is to reduce the chemical meds, if not completely, then proportionately wiht monthly testing to evaluate the blood “texture’
Yes that question was both more than one and barely a question at the same time. Since the incident in 2013 Ive suffered from PTSD and my sincerest wish is to if not have closure on this, to after 5 years, adjust his medication and see some sort of forward progress in that area. The idea of him taking this the rest of his life when it may be unnecessary is horrific.
We do not have access to a medical doctor who is also familiar with cannabis, so Peter I ask of you with your background and your education and family history with your grandfather, do you feel we are on the right track? Any advice?
My husband seems healthy but his muscle loss over the last 7 months is dramatically visible and it frightens me (him too quietly but he doesnt say much) and he is tired a lot but at the same time very active. This is an ex rugby player, full of energy who moves and is busy all day. He should not be losing muscle mass. No one can answer our questions or even nudge us in the right direction.
A nudge from you would be very much appreciated.
Without info from professionals or the highly educated, we have almost decided to take the self decision to trim a tiny bit off each of his two daily pills, say 10% and then see where that goes, but how to know? When have we crossed a line? He needs that muscle mass to take him through the rest of his life, his muscle mass at the time of the incident in 2013 is what saved his life without doubt.. he was strong and that & his fitness was in my opinion the reason he lived when 7 bloody specialists told me daily to prepare for his imminent death. Should the same thing happen today I know I would lose him. Maybe it wont happen again, there was a knee surgery then a long international flight and a synergy of events that lead to the incident in 2013, maybe we are treating for something that just wont happen again but the two drugs he is taking are in his system and maybe don’t need to be. Any thought please xx

Peter Grinspoon, MD
February 26, 2018

Hi Neva, Thank you for your comment. You situation is really complicated! I’m not sure if there is any specific study which has been done that can answer your questions. I would definitely consult with a Hematologist, ideally one who is comfortable with cannabis therapeutics, so they can see this issue from all sides. This might be hard to find but hopefully you can connect with one. I don’t have a name to give you. Best of luck!

February 23, 2018

What about Cardiovascular effects of Marijuana? There so many different opinions and contradictions in research online i dont even know what to listen to. And because its so politically polarized with politicians and special interest (Big Pharma?) i dont even know which research to believe.

Peter Grinspoon, MD
February 23, 2018

According to the National Academy of Sciences, Engineering and Medicine, “There is no evidence to support or refute a statistical association between chronic effects of cannabis use and the risk of acute myocardial infarction.” I recommend that you read any literature that purports to show any such claims very carefully because, as you alluded to in your question, this issue has become very politicized. For example, some studies may imply cannabis causes some or other ill consequence but, if you actually read the study carefully, the cannabis and the ill consequence are just randomly associated, and have no causal relationship to each other whatsoever, and may even be caused by the same root causes. The science on both sides of this issue needs to improve, and the federal government needs to lift restrictions on studying it’s medical utility.

February 21, 2018

Thank you very much for sharing this great article about Medical Cannabis. You are most welcome to take a look at this article, about the same topic:

February 18, 2018

Thank you for this blog. It is interesting as well as informative.
When a person is prescribed by her Doctor marijuana for let’s say for pain.
Does one go to the pharmacy to pick up your med?

What where are the companies that make and dispense
This drug?

Peter Grinspoon, MD
February 19, 2018

Once certified by a physician, patients typically go to a dispensary to pick up their medical cannabis. Unfortunately, it usually isn’t covered (yet) by health insurance.

Muriel Zimmer
February 18, 2018

Thank you for this wonderful article.

Please inform me of any relevant research supporting pain control of osteo arthritis and/or chronic muscle pain due to traumatic injuries using cannabis based medical products. I’d like to avoid intoxicating aspects of cannabis as it increases my anxiety.

As a Canadian I am pleased to report the legality of using cannabis is confidently striding into the near future. Keep the pressure on in the USA to legalize this plant’s use.

Thank you.

Peter Grinspoon, MD
February 19, 2018

CBD predominant strains are less likely to be anxiety producing than high THC strains. Good luck!

George M. de Vera
February 12, 2018

Hi Peter,

How about marijuana to cure diabetes? Can this lower our sugar level in our body?

Peter Grinspoon, MD
February 13, 2018

There is some interesting evidence along these lines, for example:

February 21, 2018

As per the below article “research shows it is beneficial indeed for those already diagnosed with either type 1 or 2, and especially for those who suffer complications.”

khadijah tribble
February 9, 2018

I really appreciate this piece. I’m working on the policy side over at the Kennedy School. As a SICI fellow my focus is on solving the problem of misinformation and missing information and chaos of regulating a highly politicized controlled substance. There are huge gaps in our knowledge and credible analysis of the information that is available.
We need responsible and equitable cannabis regulations that aren’t punitive to patients and consumers but doesn’t restrict the market while also mitigating the economic devastation caused by ‘war on drugs’. I’ve been looking for counterparts in at the Harvard Med School or Chan School of Public Health to be a part of the Marijuana Policy Trust think thank. Do you have any suggestions of who I should reach out to? My email is

Peter Grinspoon, MD
February 11, 2018

I can help but not via mechanism of response to comments on blog; please reach out to me via my website and I will email you back. Thank you.

February 7, 2018

Hello Peter, I am currently writing a research paper on the benefits of medical marijuana and was wondering if you could provide me with a few reliable sources, or maybe a list of benefits?

Peter Grinspoon, MD
February 8, 2018

Hi Roberto, this is a good resource:

Daniele Merkov
February 7, 2018

Is it true that marijuana can actually help to loss weight? I’ve been hearing people talk about this lately in some forum i cant remember what forum that is but i was pretty curious about they’re topic. I have been reading this marijuana strain here in and all it says that it can help you relax and chill you physically and mentally. Some of them might even help you with depression and anxiety but this issue regarding losing weight when using marijuana is just fascinating. Can you enlighten me with some new information about this?

Peter Grinspoon, MD
February 7, 2018

There is some research along those lines. This article sums it up.

Neva Morgan
February 26, 2018

Hi Daniele, Just to offer my experience. I started taking Full Extract Cannabis Oil 9 months ago (this has THC but the psychoactive effects can be avoided by weaning on very slowly, very very very slowly with tiny tiny micro doses) I hate the psychoactive effects.
I am 58 and have been obese for about 10 years. I didn’t take the Cannabis oil for weight loss as I was completely unaware of that aspect, I am taking it as an overall health aid and preventative and for balance in my endocannabinoid system. 3 tiny doses per day every day, for the last 9 months
I have lost over 40lbs during that time. Slowly gently but relentlessly downwards. I was not even aware of the weight loss as I wasn’t weighing myself, Id given up after every diet on earth, good bad and fad. One day my pants literally fell down, lucky I was at home 🙂 I realised Id lost weight, so I weighed myself and at that time about 5 months in, Id lost 15lbs. I still today cant believe it because i had genuinely given up, 58 years old and very fat with sore knees and nothing I did (diligently might I add) changed a thing, in fact everything I tried resulted in an increased weight after the fact.
Cannabis has made me lose a huge amount of weight and I am still consistently gently heading downwards.
Please note, I researched strains and studied for months and months before taking the oil, I grew my own plants and made my own Full Extract Oil with a clean solvent (ethanol) using the Rick Simpson method which is safest for home makers, except for his solvents which are not clean, so I used his method with rice cooker but I used my own choice of a clean solvent which is ethanol food grade. If you are contemplating taking this oil you need to self educate, you need to understand that the oil has THC in it and you need to wean on super slowly to use it without the horrible psychoactive feelings that the THC bring if you have not weaned on slowly, and you need to be patient once you start. But it works, it did for me and I wasn’t even trying. Might I suggest that you start with a tincture as I did until I was no longer scared of it, tincture is not as strong and is a good prelude to starting on the oil. You need to grow your own so you know what you are taking.. buying from a recreational user will not solve anything as they use all sorts of bad chemical nutrients and you wont know the strain nor will the guy selling it to you. You need to control what you are taking from beginning to end. I suggest an Indica, not Sativa as the Sativas can have an anxiety effect, well it did with me while the Indica strains are more relaxing, but the dose needs to start and remain tiny, you are not trying to treat cancer, you are not increasing your dose, you are just feeding your endocannabinoid receptors with a steady micro dose 3 times a day and your body will do the rest. Jorge Cervantes wrote a Medical Cannabis book that will assist in you growing your own indoors or out, everything from beginning to end. About 4 plants should do it, find a safe place to grow them indoors under light or outdoors if you have a secluded spot. Cervantes also gives recipes for tincture and other edibles, but eventually you should progress to the oil using the rice cooker method EXACTLY as Rick Simpson says but with a clean solvent. I have not yet stopped taking BP medication but I’ve reduced my dose under doc guidance and Id guess about 15 more pounds and Ill be off them. My doc is unaware of my cannabis taken orally but very impressed with my weight loss which he thinks is down to diet and exercise. My knees don’t ache any more.. so many things are coming back that in my obesity Id forgotten id even lost out on. bending, tying shoes, more energy, the list goes on. I accidentally lost weight by taking Full Extract Cannabis Oil with THC and Im absolutely thrilled, while at the same time waiting for something to go “ah gotcha”, and the weight loss disappear, but it hasn’t and it wont because the cannabis has had an effect on my system and restored a balance in some way I don’t understand but appreciate beyond measure. x
You need to research and study and put in the effort to learn about this topic and if you do you will be rewarded with an element of control and knowledge about why, what to do & what not to do when it comes to consuming cannabis. PS Smoking does not achieve anything, we are talking tincture or full extract oil taken orally xx

Holly Martin
February 6, 2018

How can the top Universities and colleges in the United States teach about the therapeutic, medicinal benefits of cannabis if it’s classified as schedule 1? The US government is adamant that there are none. If you, Harvard, are saying that there are benefits, how is it legal to keep the classification the same?
What is going on here?

Peter Grinspoon, MD
February 6, 2018

“Harvard” has many different faculty members who likely hold many different views on medical marijuana; this blog doesn’t attempt or purport to speak for all of them. That said, you are correct that there is a dichotomy between the the government’s classification of marijuana as having “no medical benefit” and this article which cites about a dozen areas where marijuana has been demonstrated to be beneficial. Unfortunately, our government’s policy is vastly out of step with the reality that millions of patients are experiencing, and with modern scientific evidence. It needs to change. (The history of our nation’s “War on Marijuana” is fascinating to read about; it is mostly based on racism as well as politics against the anti-Vietnam left…long story!).

February 6, 2018

A complete comprehensive article I will say. Looking at the benefits it can offer, it should be legalised. Thanks for the share.

Peter Grinspoon, MD
February 11, 2018

You are welcome!

February 4, 2018

I am 46 and have suffered from migraines for nearly 25 years. They have become less frequent ( a few per month instead of a few per week), but harder to control with rescue medications such as relpax. For 2 months in a row now I have had to take a steroid to get rid of the headache which had lasted for more than 5 days. I have tried several preventative medications over the years (lyrica, topomax, Elavil, botox, Effexor, occipital nerve block injections etc), with fleeting success. I also suffer from chronic neck tension and pain resulting from disc bulges caused by a previous accident which exacerbates the headaches.

I live in Florida and have been told that I automatically qualify for a medical marijuana card as I am a breast cancer survivor (3 years in remission). However, I am worried about the stigma and potential political/social complications of a marijuana prescription. I work full-time, have 2 small children, and am pursuing my MBA. I need to be fully functioning. Period. I am MOST concerned about any contraindications that it might have on Tamoxifen that I have been prescribed to take for 7 more years. Not sure that I can handle the anxiety of wondering, what if…

Any suggestions that you have or research that you can share would be greatly appreciated.

Thanks so much.

Jože Skrbinek
January 29, 2018

hello, my best friend have ALS disease. Do you have any experiance with this disease, medical CANABIS-ALS. He is 55 years old.
Thanks for answer.

best regards from Slovenia

Peter Grinspoon, MD
January 29, 2018

There is some scientific evidence for this benefit, such as the following article:

There is a huge amount of anecdotal evidence that it helps people, certainly with their symptoms, but it really needs to be studied more rigorously.

Lisa M Kaelin
January 29, 2018

I’m 58 years and have been battling brain inflammatory disease. 20 years of autoimmune diseases, surgeries, every type of inflammatory disease and many prescriptions. Finally enough bullshit!!! I took my life in my own hands cold turkey off 20 years of pills. Maybe not the smartest thing to do however with weed I did it. I can’t believe how functional I have become. Not cured but I can manage my life with weed and probiotics. I have my brain back. My pain is way down. I don’t cry anymore about being sick. I’m not in a fetal position from pain. No one needs to suffer…it’s not like they will give you a medal for it. Weed is life changing and healing and hopeful!!

Peter Grinspoon, MD
January 29, 2018

Glad that you found relief from your symptoms. Certainly, you are not alone, which is why doctors and patients need to become better educated on this topic, and more research needs to be done!

P L Burr
January 23, 2018

Isn’t smoking ANY substance but for your lungs?

Peter Grinspoon, MD
January 23, 2018

There are many different ways to consume medical marijuana: drops under the tongue, edibles, tinctures, vaporizing it, topical treatments; it is not recommended (at least by doctors…) that people smoke it (though, interestingly, it hasn’t been linked to lung cancer in the studies I’ve seen).

Elizabeth Pallett
January 22, 2018

OK lets begin by removing a couple of things, the medical/recreational and more importantly get rid of the marijuana prohibition term, use the plants correct name and then perhaps patients might not be so confused, its name is Cannabis.

All Cannabis should be grown organically, never have the males removed and the object is to gain as many of the 140 cannabinoids as possible to bring about whole health.

How the oils and tinctures are made are very important and given the USA is getting it completely wrong and are now years behind what we in the Cannabis compassion suppliers are finding and now know.

The research is being done, it is simply not being done by big pharma or governments.

There is absolutely no health or safety risk using Cannabis from conception to the grave. Anyone and everyone should be able to grow the plant and use it as they please as you should any other herb or vegetable, it should not be on a drugs list and it should not be under the control of drug companies or the medical profession.

Time to end the war on a plant and heal the planet.

Peter Grinspoon, MD
January 22, 2018

My father is Dr. Lester Grinspoon, the “grandfather” of medical marijuana (a.k.a. cannabis), who has been fighting to legalize this ever since his book ‘Marihuana Reconsidered’ [sic] came out in 1971, so I’m not unsympathetic to your position. 🙂

Sonny Chandler
January 22, 2018

If THC is removed, is there pain relief? In other words — is there pain relief and PTSD help etc. etc when the THC chemical that makes people high removed from medical marihuana ?

Peter Grinspoon, MD
January 22, 2018

There are many compounds in marijuana so THC isn’t everything but, that said, I believe that it is a fairly important component in pain control. CBD, another cannabinoid, does have pain controlling effects as well, without the psychoactive effects.

Justin Escher Alpert
January 22, 2018

“We can only hope that within the next decade the effects of the “war on drugs” will start to fade and give way to a more comprehensive and fact-based understanding of all bioactive substances. So whether you reach for the medicine bottle or the lighter, you’ll understand just how each dose will affect you, the benefits and risks of consumption, and the potential for abuse—and, however you choose to use these substances, you’ll have greater assistance from our health care system and a more open-minded society to support your choices.” –

Peter Grinspoon, MD
January 22, 2018

Well said! Agree the “War on Drugs” is 100% counterproductive. Thanks for the interesting article.

January 22, 2018

Hi Peter,

It is a very emotive subject. As I see as Governments etc can make money from medical marijuana then they will take it on board. It is a nonsense that the large pharma countries are legally killing people and it is only recently that many of us are waking up to natural medicine. Take the large alcohol manufacturers, lover the world over by Governments and their paymasters as it generates so much revenue for them. This is despite the devastation that this drug causes to some many families the world over.


Peter Grinspoon, MD
January 22, 2018

Hi Joe, thank you for your comments. I agree that marijuana is safer than alcohol!

Cat Motors
January 19, 2018

Hi Peter!
Tell me please, is there any statistics on how the number of traffic accidents has changed after some states of the USA have allowed the use of marijuana? It would be interesting to know statistics on cars and motorcycles. We stay in Chiang Mai (Thailand), and sometime have are heated discussions and disputes about this among rental owners =)

Peter Grinspoon, MD
January 19, 2018

People shouldn’t drive when they have used ANY medicine or substance with psychoactive effects including cannabis. This study from NIH (National Institute of Health) shows impairment but not as dangerous as alcohol (which is a good summary of marijuana in general…)

Sara Scotti
January 20, 2018

There are studies on this exact topic! This is a recent article looking at two studies. I find more weight in the study conducted by AJPH, in part because it is more extensive. Of course driving impaired is not to be condoned and this is a topic worth researching.

Valerie Tikhonoff
January 18, 2018

Information on drugs interaction are rare. Do you know the intersections with new oral anticoagulants such as Apixaban? One of my patient with ALS got a recurrent pulmonary embolism on treatment with apixaban and oil cannabis.

Peter Grinspoon, MD
January 18, 2018

This needs to be studied and is exactly why the government needs to take marijuana off of “schedule one” so that it can be studied. Given how new the oral anticoagulants are, I don’t think it’s been studied yet. The case you cite could just be treatment failure and have nothing to do with the cannabis…

Mimi Conners
January 27, 2018

I just found this. It seems relatively up to date.

January 17, 2018

Cannabis oil extraction is advancing quite dramatically as well. The cannabinoids and terpenes can be extracted in a number of ways including ethanol/hydrocarbon soak, distillation, even a press (similar to a t-shirt press) using heat and pressure to literally squeeze the oils out of the cured flowers. The healing properties of these oils can even be recombined to specifically treat different types of ailments. What is needed, is more information to identify which compound from the plant that is aiding their specific ailment. Even if someone has not had a beneficial experience with one of the strains they have chosen to use, there is a myriad of other strains with different ratios/percentages of terpenes/cannabinoids. Genetic profiles of strains are even being mapped to aid researchers in identifying which may best be helpful to patients in the future.

Peter Grinspoon, MD
January 17, 2018

Thank you for your interesting comment!

Harry Conroy
February 8, 2018

To Alfonso and others interested,
What about Rick Simpson Oil ( R.S.O. ) ?
I reference the life experience of Canadian entertainer Alan Park
( Royal Canadian Air Farce sketch comedy ensemble, popular national Canadian comedy television show ).
He used RSO in a suppository form and purportedly reduced his
psa blood test from around 700 to close to zero, over maybe a five
month period !
He was diagnosed at stage four prostate cancer after going to the
Doctor for an unrelated complaint, and subsequent diagnostic tests
revealed his totally unsuspected, and late stage, prostate cancer.
He apparently could not be offered any conventional treatment
per the assessment of his Physician due to the advanced stage
of his prostate cancer condition.
The Doctor gave him about three months to live. He has celebrated
three years of survival since that initial cancer diagnosis.
Rick Simpson is a Canadian citizen that apparently has been under
legal duress associated with his total marijuana plant conversion
to oil concentrate of some sort. Alan Park uses the RSO in suppository
Alan Park has an online pod cast called, GREEN CRUSH, which
is related to marijuana issues, medical marijuana, and his
personal experiences.
If his health story journey is accurate, and positively in support of prostate cancer
treatment in a genuinely efficacious and measurably evidenced
based way, we should get our interest directed in this area
of inquiry, most ricky ticky !
It certainly sounds compelling to me, at least on the face of his
narrative of his very unconventional personal experience and

SAM Action
January 16, 2018

Doctors are the leading cause of Opioid addiction in America. They continue to prescribe Oxycontin like it was candy and then after the prescription runs out, their patients turn to the only available alternative; Afghanistan grown US Military protected Heroin. The greatest threat to American youth is the ignorance and arrogance of the AMA and a Federal Government that refuses to consider Marijuana as an adjuvant for pain mitigation.

Shame on us for tolerating a corrupt alcohol-based establishment and perpetuating the 1937 Nazi-era marijuana prohibition laws.

Rona Clayton
January 16, 2018

I agree fortunately I never took opiates until I was legally prescribed them in 2004 after a MRI and my diagnosis for back pain and in my town we don’t have heroin and yes I was on oxycontin years ago and when I had to detox off of them due to unfortunate circumstances I thought I was dying I never want to experience that again

Craig Gillette
January 15, 2018

I’ve been using DC medical marijuana for four years now, to treat my fibromyalgia, other health issues, and even my addiction recovery. Marijuana is non-toxic and safe to use every day, and I’m having great success with it. So are millions of others of people. Pills kill, cannabis heals. I’ve been smoking cannabis for four decades, I don’t need no scientist or Dr. to tell me the magic that it contains. They need to convince and educate themselves. They need to remember the Hippocratic oath to first do no harm, and death pills are killing people every 15 minutes in America. Stop with the pills already !!!!!!

Peter Grinspoon, MD
January 15, 2018

Glad you found the treatment that works for you!

Commenting has been closed for this post.

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