My short bio: Hi everyone! My name is Ethan Russo, and I’m here to answer your questions about cannabis (AKA marijuana) as it relates to chronic pain.

I’m a board-certified neurologist, psychopharmacology researcher, and Medical Director of PHYTECS, a biotechnology company researching and developing approaches targeting the human endocannabinoid system (ECS), which is a homeostatic regulator of physiology. That is to say, it helps keep bodily functions in balance, which is frequently the case in situations of chronic pain.

I was a clinical neurologist in Missoula, Montana for 20 years in a practice with a strong chronic pain component. In 1995, I pursued a 3-month sabbatical doing ethnobotanical research with the Machiguenga people in Parque Nacional del Manu, Peru. I came back from that experience with a much greater appreciation of the integral role that plant medicine should play in modern therapeutics, and incorporated herbs and cannabis into my practice. In the subsequent 20 years, I have pursued research in these areas.

In the course of this work, I became President of the International Cannabinoid Research Society, and Chairman of the International Association for Cannabinoid Medicines. I currently serve on the Scientific Advisory Board for the American Botanical Council.

I’m author of Handbook of Psychotropic Herbs, co-editor of Cannabis and Cannabinoids: Pharmacology, Toxicology and Therapeutic Potential, and author of The Last Sorcerer: Echoes of the Rainforest.

I’m also the founding editor of Journal of Cannabis Therapeutics, selections of which were published as books: Cannabis Therapeutics in HIV/AIDS, Women and Cannabis: Medicine, Science and Sociology, Cannabis: From Pariah to Prescription, and Handbook of Cannabis Therapeutics: From Bench to Bedside.

I’m here on behalf of Pain BC, a collaborative non-profit organization made up of people in pain, healthcare providers, and leaders from universities, government, business and the non-profit sector. Pain BC strives to improve the lives of people in pain through education, empowerment and innovation.

Please Remember… The content provided here is for informational purposes only. It’s not intended to be a substitute for professional medical advice, diagnosis treatment or care. We encourage everyone to seek the advice of qualified healthcare providers if you have any questions regarding the content of this show.

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My Proof:

Edit: Thank you so much for your questions everybody--I hope I was able to provide some helpful answers. I have to run now, but I'll try and check back in the next week or so to answer the remaining questions.

Comments: 223 • Responses: 82  • Date: 

tangentcentric17 karma

I have read that cannabis can help and hurt SWS Slow wave sleep, and the quality of deep restorative sleep, which is an issue for many of us with chronic pain/fibromyalgia. Is there any scientific evidence which supports either position?

Ethan_Russo26 karma

What cannabis does do is reduce REM (dreaming) sleep. This is helpful for those with intrusive nightmares, as in post-traumatic stress disorder. In general, cannabis used medicinally helps sleep quite effectively by reducing symptoms of pain, spasm, etc., that tend to disrupt it. You can search this page for an article on cannabinoid and sleep:

DriftwoodSeashell4 karma

Would cannabis for sleep be less harmful than something like zopiclone (which also seems to reduce REM) every night? Are there any strains/types that would not reduce REM?

Ethan_Russo7 karma

Many sedatives reduce REM-sleep. CBD may not be as likely to have such an effect.

pdxcannabusiness11 karma

Do you have any research suggesting a relationship between the endocannabanoid system and it's role in hypokalemic periodic paralysis?

Edit: very poorly worded. But I think you get where I am going.

Ethan_Russo8 karma

Great question---I know the condition, but no specific work has been done with cannabinoids. There may be online attestations.

Confidence_Analytics10 karma

It seems to me, one rather large difficulty with medical cannabis prescription is a lack of method for meeting the western prescriptive model. In Western studies of cannabinoids for therapeutic use, study after study continues to focus on a single analyte, where it is clear to those of us in the industry that benefits arise from a broad spectrum of cooperative analytes in varying chemotypical ratios. How do we convince larger research institutions to pursue this approach, despite its complexities? How do we, as analytical cannabis laboratories with big data (e.g. multi-spectral, microbial, genes, cannabinoid, terpene, alkanes, etc) on 50,000+ examined samples contribute to clinical science without bumping into the federal fear that some large educational institutions seem to not be able to shake?

Ethan_Russo10 karma

Complex issue. Pharmaceutical companies prefer single molecular entities of their own device that can be patented and protected. Botanicals, such as cannabis, are the way of history and remain the approach for much of the rest of the world. Labs and dispensaries can collect and mine data to form correlations, but this is very difficult and does not convince Health Canada or the FDA. Only randomized controlled trials do that.

phiber_optic0n9 karma

Does cannabis have any application for treating traumatic brain injuries?

Ethan_Russo15 karma

This is a very complex topic. TBI is a multi-pronged challenge, producing migraine-like headaches, dizziness, nausea, memory problems, emotional lability, etc. It is my experience as a neurologist that very low doses of cannabis help with various symptoms. Additionally, both THC and CBD produce neuroprotective effects that could be helpful. Anecdotally, some football players with chronic traumatic encephalopathy report benefit, as well. No formal studies have been done.

McDain9 karma

Hi Ethan: You have stated that strain names are unimportant with regard to cannabinoid and terpene content. I am particularly interested in your assertion that myrcene is responsible for the couch lock effect of cannabis. Do you know of any human research that supports this?

Ethan_Russo21 karma

Yes, this came from the sum of the evidence of myrcene being sedating in animal models, plus work done in humans with pure THC and pure myrcene. That is anecdotal evidence, however, that we hope to confirm in double-blind randomized clinical trials. Here is a link to an article:

Strain names would be important if they were consistent across the industry, but that is certainly not the case. Hopefully, someday, the medical or even recreational consumer will have access to reliable lab assays stating cannabinoid and terpenoid content of the material.

nicoleflemming5 karma

Is what your saying is that there is no way for a consumer to know what strains have less myrcene?

Ethan_Russo11 karma

There would be if there were reliable assays on the same material, not on something else that was tested 6 months ago.

freshleaf935 karma

Mangos have myrcene just like weed. Some people eat a mango before smoking to increase their high.

Ethan_Russo2 karma

I doubt that mango-eating will materially affect the high. Mangoes vary greatly in their myrcene content:

and most terpenoids seem to be far less active taken orally than they are when inhaled.

GalacticCow8 karma

I've heard varying accounts about the addictiveness (or lack thereof) of cannabis oil and smoked marijuana. From an informed scientific standpoint, is cannabis considered an addictive substance or not? Is there any risk of developing addiction to it with regular use (especially used in a medicinal capacity to treat chronic pain)?

Ethan_Russo16 karma

In the scheme of things, cannabis is less addictive than cigarettes, alcohol, opioids, amphetamines or cocaine. There are people who develop chronic use, would like to stop, but find that they cannot. The figure in the literature is that 9% of people who start cannabis will develop dependency, but at least in the USA, these figures are skewed by the fact that over 50% of people in treatment for cannabis dependence are there by court order. Concentrates, and oils are much more likely to produce tolerance and other problems. The faster a drug gets in (e.g, inhalation) the more rapidly it reaches the brain, producing greater intoxication and the possibility of reinforcement.

ashmcfarlane7 karma

Hi Ethan, I am wondering how readily available cannabis oil is to people suffering from chronic pain? Personally knowing how addictive pain medication can be, how addictive is cannabis oil? And are there any known long term side effects from regular use? Thanks for giving the opportunity to ask questions.

Ethan_Russo8 karma

Again, these oils are becoming prevalent, but one must know their source, composition, to have any idea about dosing. Concentrates are associated with numerous issues, and may contain residual toxic solvents, pesticide residues, etc. Normally, they are far more potent than is needed to control pain or other common symptoms. Where concentrates have their best place is primary treatment of cancer. Use of concentrates may predispose toward orthostatic hypotension (passing out while standing), panic reactions, and development of tolerance. I would tread lightly, if at all.

stroudwes1 karma

So would there be possible long term side effects of concentrates due to the possibility of other ingredients in the concentrates?

Ethan_Russo2 karma

Yes, if there are toxic elements in a concentrate, the potential problems associated with its use will be compounded by taking it regularly.

the_good_time_mouse6 karma

I find high CBD cannabis very effective for pain and social anxiety (especially since it doesn't get me high, so I can go to work etc). However every time I've tried replacing my regular cannabis with it for a few a week or so, it causes me to have very specific episodic memory problems. It has happened several times - every time I've tried high CBD cannabis - enough for me to be convinced the CBD is the cause.

I've not heard anyone discuss this reaction before: do you have any insight?

Fwiw, apart from a chronic pain injury and social anxiety, I'm otherwise healthy and not dealing with and mental or neurological problems.

Ethan_Russo7 karma

I have no reason to think that CBD is actually the culprit. Most "high-CBD" strains in commerce also have a lot of THC, which is well known to affect short-term memory adversely. High-CBD strains also tend to be high in myrcene, which is sedating. A strain that has a good titer of alpha-pinene may reduce short-term memory impairment from THC. See: Taming THC article:

the_good_time_mouse3 karma

  • The strains involved had much lower THC than normal. As I mentioned, often the 'high' would be very subtle.
  • The memory issues wouldn't actually happen when I was high, but tended to be 12-24 hours later - sometime in the next day. I'd suddenly lose the last 5 minutes or so of my memory.

It hasn't happened since, never happened before, and happened several times over the course of a couple of years. I kept coming back because the CBD was so profoundly effective, and the side effects, while disturbing, were minor.

Ethan_Russo5 karma

Trial and error will be required.

smackthisaccountdown6 karma

Whenever I used to smoke and try to relax, I would get very anxious, almost to the point of panic. Is there a neurophysiological difference between those who feel alleviated with THC and those who feel anxious/paranoid they're going to die? Basically, is it a "me" thing? Thanks for doing this AMA!

Ethan_Russo3 karma

People respond differently to cannabis, and especially THC. Some of this depends on what is called "endocannabinoid tone," a function of how active or inactive the endocannabinoid system is. THC is well known for biphasic effects---a small dose may alleviate anxiety, while high doses certainly can provoke it.

Xiphias_5 karma

I see many people cheer when cannabis is accepted medically for treating pain in states and countries. Are there any benefits of using cannabis compared to traditional painkillers such as Paracetamol and Ibuprofen?

Ethan_Russo7 karma

They are very different. Paracetamol (acetaminophen) is a pretty weak painkiller and is dangerous in high chronic dosing. Ibuprofen and other non-steroidal anti-inflammatory drugs have their place, but lead to ulcers, intestinal bleeding and other serious side effects. We need more research on cannabinoids to show their proper place in the scheme of chronic pain treatment.

tangentcentric5 karma

I get the best relief for pain and sleep problems from edible forms of cannabis. However, if I need to travel outside the country I am forced to resort to THC in pill form (nabilone/cesamet) because obviously I cannot take cannabis across borders. I find that taking nabilone has some very negative side effects--extreme lethargy and extreme cognitive impairment--that last over a longer duration (up to 2 days). Do you know a way of mitigating the negative effects of nabilone? Or is it safer to avoid it altogether (in favor of non-cannabis alternatives) when I do not have access?

Ethan_Russo4 karma

Nabilone is a synthetic analogue of THC that is 10-times more potent. It is hard to say what might help, if anything. Many people feel similarly to your experience.

bobbyby3 karma

Hi Ethan, I suffer from idiopathic intracranial hypertension. from experience i know that marihuana has a positive effect on those headaches that iih causes. does marihuna help lower the pressure or just numbs the pain?

Ethan_Russo5 karma

There is one case report of benefit on reducing pressure. See PubMed, National Library of Medicine. It has not be formally studied, and would be a hard thing to do, I'm afraid.

RRARyan3 karma

What types of chronic pain does cannabis have the best positive effects, and which have no effect?

Ethan_Russo7 karma

Good question. Cannabis shines in treating neuropathic pain. It is also very good in cancer pain. CBD strains would be especially applicable to arthritic conditions. Cannabis is not very effective for acute pain: toothache, broken leg.

RRARyan2 karma

The use of cannabis in combination with opioids appears to enhance the analgesic effects and allow for lower amounts of opioids to control pain. Have there been any additional reports or studies since the JAMA 2014 publication [ Medical Cannabis Laws and Opioid Analgesic Overdose Mortality in the United States, 1999-2010 by Bachhuber, Saloner, Cunningham,& Barry ] that support the lower overdose in the various political boundaries that permit cannabis use?

Ethan_Russo2 karma

See pain chapter in the publication list.

21organiccaveman2 karma

Hello, I have been using medical cannabis to treat IBS and chronic pain including sciatica, neck and shoulder pinched nerves and damage. Finding a lot of inconclusive information Imnjnrerestsd to know more about the other cannabanoids than THC and CBD as well as terpenes and thier effects. As I've noted CBD levels in most med. cannabis to be less than .05% and noting CBC, CBG in much greater concentrations between .25-1.25% may play a much bigger role in the various effects of different strains. So my 2 part question is first to ask about a greater explanation of the effects of these lesser known cannabanoids and secondly if there are any cannabanoid or terpenes or combinations of them that would be particularly good for my spastic colon issues and nerve / related muscle pain?

Ethan_Russo6 karma

This link will provide more details about the medical attributes of various cannabinoids and terpenoids. There is also a page here that links to most of my articles and book chapters: Please look for the chapter with Andrea Hohmann that discusses this specifically in relation to pain. I'm afraid that CBD is hard to find in many areas, and there must be a lot of it to make a difference. You are unlikely to see high titers of any cannabinoid beyond THC and CBD. The terpenoid with the best pain profile is caryophyllene, that is a non-sedating anti-inflammatory and analgesic. Many cannabis extracts will have a good amount of this, but reliable information is often hard to find for the potential consumer. Spastic colon, or irritable bowel syndrome, responds to THC strains, but there is every reason to believe that CBD will also be of benefit.

Omegma2 karma

Is the use of marijuana contra-indicated for help with sleep when there is a history of estrogen-positive breast cancer?

Ethan_Russo3 karma

Not that I can see.

Omegma1 karma

I thought there was a risk that marijuana would increase estrogen levels?

Ethan_Russo3 karma

See response elsewhere. There are no endocrine changes with chronic use medically to our awareness.

LeaninKeenan2 karma

Hi Ethan!

I am wondering if we know the long term effects of marijuana on a child pre birth, as in 'if mom smokes or consumes while pregnant, what could happen?"

Ethan_Russo7 karma

"No drug is the best drug in pregnancy." However, there is no evidence of cannabis producing birth defects. There have been a couple of studies showing slight decreases in birth weight, but these are not always well controlled for other substance use, prenatal care, nutrition, etc. Cannabis was extensively used in the past for OB-GYN conditions. See article here: It is a situation where the needs must be weighed against the risk. In this instance, the law looks very unkindly on the practice and absolute caution is necessary.

JontyDante2 karma

Hi Ethan, thank you for this AMA. I smoked skunk for over 14 years and for the last 5 of those I had what some call paranoid schizophrenia. Psychotic episodes where I would hallucinate people chasing me with weapons. Also aggressive voices in my head for years. I was forced to stop smoking and it took years for those problems to go away. What is your opinion on this and the use of marijuana regarding a persons long term mental health?

Ethan_Russo8 karma

This is a very complicated topic. THC is associated with triggering psychosis in susceptible people, but there is no proof that it will cause it de novo, or else there would have been an explosion of cases starting in the 1960's. Interestingly, cannabidiol is very helpful in treating such symptoms. One clinical trial is published, and another one should be soon.

oDRKo2 karma

Thank you for taking the time to do this AMA. So I know someone who has scoliosis, arthritis, chronic pain, etc. Lets call her jenny(not real name). Jenny has been going to a pain clinic in a non legalized (but medical) state. They found cannabis in her blood work and refused to renew her script for opiates and said the reason being, "a known interaction between the two that makes it unsafe in combination." They refused to give her a prescription unless jenny has no Cannabis in her system.
My questions: What is the interaction between opiates and cannabis if there is one? If there isn't a known dangerous interaction, is this a political move by the pain clinic to cover their arse? It seems silly to me that a "pain clinic" would be so against the use of cannabis, and I have suggested she go to another clinic.

Ethan_Russo10 karma

When I speak to neurologists and pain specialists about this issue, I point out that the pain control from opioids and cannabinoids are additive, and even synergistic. While the combination could produce greater sedation, this is not commonly the case, and there is no specific contraindication to using them together. Please see the book chapter with Andrea Hohmann listed here:

Many chronic pain patients report "opioid sparing" with use of cannabis and are able to lower their dosage.

skyhigh3042 karma

I have seen online that producers of hemp oil claim that it has high levels of CBD. Is there any truth to this claim?

If not, are there any legal sources of CBD based pain relief, particularly non-prescription, for places where marijuana is still not currently legal?

I have found great pain relief of chronic pain from a traumatic injury with the use of high CBD strains(Indicas), and very little from high THC strains (Sativas), but live in a location where I do not have access to reliable medical marijuana.

alexanderknox2 karma

Yes you can order CBD products online from many distributors in Colorado. Friend's grandpa recently passed away due to CBD (Corticobasal Degeneration) and they were buying some 30mg CBD sublingual tinctures for him - he noted massive relief and it was the only medicine he ever willingly took.

Ethan_Russo2 karma

Despite all info to the contrary, cannabidiol remains Schedule I and illegal in the USA. There is massive fraud in the industry with many samples containing no CBD or much less than advertised.

nicoleflemming2 karma

I have just learned about using cannabis oil in the form of a suppository. What dose/amount of oil should I start with for Chronic nerve and osteoarthritic pain? How much per day.. I can only find the dose for curing cancer and I believe that would be a stronger daily dose then for pain. Thank you so much for offering this opportunity to ask questions

Ethan_Russo4 karma

It is not practical to give guidelines in this situation without knowing the exact composition of the material. Unfortunately, the quality control in the industry in North America is wanting in many instances. Only one LP in Canada is offering concentrates at present, if I'm not mistaken. My advice on dosing is always, "Start low and go slow." People should always titrate (adjust dose upwards) based on control of their symptoms, not to the point of feeling intoxicated (high).

nicoleflemming2 karma

Thank you.. I am trying to avoid the high... so this method is the perfect solution for me.. Thank you

Ethan_Russo5 karma

CBD-containing strains are excellent for pain and inflammation and may represent an attractive alternative for people with chronic pain that wish to have relief with less likelihood of impairment from THC, so that they can work or study.

[deleted]1 karma


Ethan_Russo3 karma

Sorry, I cannot vouch for any particular strain. Rather, a reliable analysis must accompany the material. Ask for it.

ranchochupacabrash2 karma

Hi Ethan, I have a few questions today. Are there any particular strains that have more beneficial effects for people with wasting syndrome? Can isolated trichome heads be decarboxylated independently? Where do you see the future of solventless cannabis concentrates in the next five years? Thank you for doing this ama Dr. Russo.

Ethan_Russo3 karma

Wasting syndromes have long been treated with THC or high-THC cannabis. There are various ways of decarboxylation. The time required to do this depends on the temperature. Right now the best concentrates are hashish or extracts made from CO2 or ethanol.

ranchochupacabrash1 karma

Thank you for the response. How long would proper decarboxylation take at 170°f using sous vide? Or are there any better methods of decarboxylation?

Ethan_Russo3 karma

I have an old article circa 1990 that would seem to indicate that 4 hours at 180 degrees Fahrenheit should work. Higher temperatures require much shorter times, but tend to reduce terpenoid and even cannabinoid content.

alexanderknox1 karma

Thank you VERY much for your research, work, and efforts.. So many of us need you and thank you.

My story is tough to tell I'll try to be as short as possible, I'm sorry for the length.

I have a medical... "issue" we'll say. I have been all over the western states visiting hospitals and clinics. UCLA, USC Keck, multiple Mayo Clinics, and nearly every central California guy available. I was diagnosed with a neurocardiogenic syncope three years ago at age 19. But I do not believe that's the totality of my issues, as my symptoms are sometimes different than commonly known NCS symptoms and nobody knew mmj helped NCS sufferers.

-Cardio from UCLA and USC Keck, local people as well. (NCS was FINALLY diagnosed by a local guy using a tilt table test after 7 years of passing out and 2 years of constant hospital visits) -Neuro and some endocrinology from Mayo Clinic in Scottsdale and Phoenix.

I passed out for the first time 6 years before diagnosis, at age 12. I passed out 2-4 sometimes more times per day. But come senior year of high school, I wasn't having nearly as many issues.

I didn't start frequently smoking marijuana until my senior year, but didn't notice the correlation between my improved health and my increased marijuana usage. I moved away to college thinking I had mostly outgrown my passing out issue (still undiagnosed at the time) as my family practitioner hypothesized I would, though my parents were very tentative because of my health issues.

Once at school in AZ I needed to a job for basic college expenditures - I had to stop smoking. I began passing out about a week after my last cannabis consumption, this time having symptoms never previously experienced.. i.e. random extremities going numb, hot one minute cold the next, blurry vision, light sensitive migraines from HELL.. But I made the connection. I smoked that night, called my parents, told em, and moved home. Then came all the doctors visits like a 10 day stay at UCLA for an observed EEG, EKG, USC appointments, etc, revealed nothing. All of my doctor visits, all the prescriptions, none of it helped. I was still passing out and experiencing weird symptoms. I eventually became so fed up with the inexplicability that I committed to smoking marijuana and have since had about 5% of the issues, I'd guess. I quit going to doctors, quit taking medications (of ANY kind), and have been living an awesome life since.

My only questions to you are why does marijuana help me so much? I've met no doctor that can explain ANYTHING regarding my medical marijuana use to me. Do you have any advice/recommendations, or any questions for me since I seem kind of question mark-ish to hospitals and clinics?

If you read all this thank you so so so much.. Blessings.

Ethan_Russo1 karma

This condition is very rare, and as such, it is often hard to find good data, and certainly no formal studies have been done. However, I know of at least one other person with a similar story who has been helped by cannabis. The explanation? Cannabis works upon the endocannabinoid system, a major homeostatic regulatory system in the body affecting almost every aspect of our physiology. It is designed to maintain balance. When a system is out of that balance, it tends to help it to equilibrate once more.

Cleverest_Epithet1 karma

Is it possible for people diagnosed with Bi-polar or schizophrenia/schizoaffective disorder to enjoy recreational marijuana?

How do marijuana and anti-psychotics mix?

Ethan_Russo1 karma

This is one of those double-edged sword situations. While cannabis has been associated with triggering psychosis in susceptible individuals, it also can alleviate symptoms in some, particularly cannabidiol. There have been case reports of benefit in bipolar disease for cannabis as well. Do a search in PubMed/National Library of Medicine.

bombsaway19791 karma

Hi Ethan. Really interested to learn more about CBD, as I've encountered a ton of positive anecdotal stories about it's efficacy. I've heard it doesn't need to be heat-activated in order to work....I was curious about dosage, for juicing plants versus extracting to Rick Simpson oil or something. I know the studies are still on-going, but I want to know how strong of a dose a person would need to say, combat cancer. And HOW it combats cancer/works in your body. I know there's a lot of CBD research being done in you have any CBD resources you could refer me to if I'd like to learn more about what it actually does (neurologically & physiologically), or access scientific studies on it?

Ethan_Russo1 karma

See responses above. There is no CBD to speak of in raw cannabis, but may be CBDA, depending on the strain. Doses of cannabinoids required for primary treatment of cancer tend to be quite high. All of the phytocannabinoids (plant-based cannabinoids) have the property of killing cancer cells while being non-toxic for normal cells, quite a departure from standard chemotherapy agents that are toxic in general. PubMed search will help you find many references.

triplehelix_1 karma

what are your thoughts on nootropics?

Ethan_Russo1 karma

Clearly off subject. I believe in improving one's mind by clean living, exercise and good diet, supplemented by medicine where needed, and preferably herbal-based when appropriate.

Cornsoup1 karma

How about dystonia? Or more generally, cerebral palsy?

Ethan_Russo1 karma

Dystonia is tough to treat in any event, and there have been minimal reports with cannabis. With CP, there is good evidence for benefit on spasticity treatment and clinical trials are ongoing right now with Sativex in affected children.

fwr12141 karma

I suffer from essential tremors I don't drink or do drugs could a specific type of medical marijuana help me? My tremors interfere with almost everything in my life.

Ethan_Russo1 karma

Tremor is tricky with respect to cannabis. Isolated patients have reported benefit, while many see none.

Astyanax011 karma


When, in your opinion, will MS be actually cured, such that I could have an op/take a pill and have it wrapped up in a day/week?


Ethan_Russo1 karma

I would have hope that we'd be there by now. It seems to be a multi-factorial disease. You may wish to look into new theories on the gut-brain axis, and prebiotic/probiotic approaches to its treatment.

DesinasIneptire1 karma

Hi, I'm an addiction doc, and clinical pharmacologist, but nonetheless I'm quite ignorant on medical use of cannabis, always having seen in as a problem for my clients. Can you point me to some good and comprehensive review papers? Thanks

Ethan_Russo1 karma

Please start with the Taming THC article and pain chapter with Andrea Hohmann in the publication list:

sourmilksmell1 karma

I'm late to the party. Is there any benefit for an older guy like myself that has osteoarthritis in my knees?

Most pain meds put a person down, but I like to be active.

Ethan_Russo1 karma

There are some recent reports based on animal studies that suggest an important role of the CB1 receptor in pain from osteoarthritis. CBD has multiple anti-inflammatory attributes, as well. The work done clinically to date also suggests a place for such treatment.

Oppo841 karma

Thanks for doing this Ethan, hopefully you pick this up on your way back round.

Someone close to me suffers non-refractive tonic-clonic seizures, which have twice now brought on periods (months) of psychosis. No medication is really working to suppress things, so they are weighing up stem cell therapy in Europe.

My question is, how is research going with regards to seizures and cannabinoids?

Ethan_Russo1 karma

This is quite advanced, actually. Epidiolex, the CBD-based medicine, is close to FDA approval for epilepsy associated with Dravet and Lennox-Gastaut syndromes. Additional work is beginning with CBDV. The future may be bright in this area.

x4nthous1 karma

For years there have been arguments regarding possible damage to the brain due to adolescent cannabis smoking. This has led to large debate regarding adolescent medical marijuana usage. There seems to be many conflicting studies regarding this topic. Do you believe adolescents should have access to medical marijuana as opposed to prescription painkillers and opiates if deemed necessary for pain?

Ethan_Russo2 karma

There is a world of difference between recreational use of cannabis, sometimes with chronic high dose exposure, and the use of low doses to treat a serious disease. I have no moral or ethical problem with the prospect of cannabis-based medicines to treat adolescents, children, infants or pregnant mothers when the need arises. It has been done throughout history until recently, and then as now, the physician must weigh the pros and cons in open discussion with the patient and their family (as appropriate).

Agamoomnon1 karma

What are the chances of cannabis use creating social anxiety in an individual, have there ever been any links between them?

Ethan_Russo1 karma

THC/cannabis may alleviate anxiety at very low doses, but certainly can exacerbate it at higher doses. CBD is anti-anxiety.

javabakedcakes1 karma

My grandfather is a retired medical doctor and he has multiple myeloma. His doctors can do nothing for him at this time but manage his pain as he dies. How can we convince him to try medical marijuana to help ease his pain? He can barely hold a conversation due the amount of narcotics he is on and many in my family would like him to try medical marijuana in an effort to allow him the ability to communicate with us in his final days/weeks. Is there any specific study we could show him that might convince him to at least try it? He is fairly lucid for 15-20 minutes 4 times a day and that is it.

Ethan_Russo1 karma

Please see the pain chapter in the publication list. Also look for studies on Sativex and cancer pain by Johnson and Portenoy on the PubMed search page.

HOTandBIG1 karma

Cannabis has the opposite effect on me compared to most others. I get energy, can't sit still, can't fall asleep and my true feelings/emotions come out. Any ideas as to why I'm so weird?

Ethan_Russo1 karma

People respond differently to others, and it may also be a function of the biochemical composition of the strain.

Nyakbag1 karma

Hello from Holland. I was successfully treated for HCV years ago using conventional therapy and have been undetectable since. I have in the meantime been diagnosed with depression, ptsd as well as osteoartritis in both shoulders and hands. I do not take my prescription pills (mirtazapine, alprazolam, painkillers). I do smoke cannabis regularly. My question is, can cannabis alone cause a lot of liver damage? PS. I recently took Ayahuasca and found it very helpful for my mental problems. On another occasion I took rapé, and sananga. These were genuinely healing experiences for me. The Amazon is full of helpful medicinal plants. I wish they could be more readily available in Europe.

Ethan_Russo3 karma

Some reports have linked THC to hepatic fibrosis, but CBD and caryophyllene actually can counteract such tendencies.

420divarx1 karma

What is the corelation between the ECS and the endocrince system? My hubby has pheochromocytoma and Neurofibromatosis

Ethan_Russo3 karma

There are anecdotal reports of cannabis helping symptoms of pheochromocytoma, but no formal studies. Neurofibromatosis is a very complex disorder, which again, has not been studies specifically with cannabinoids. While cannabis does produce acute changes in hormone levels, these tend to stabilize with regular usage in patients that need it medicinally.

dr1nkycr0w1 karma

What hormone changes does it produce?

Ethan_Russo2 karma

There are various reports of acute changes caused by cannabis in hormone levels, but they do not persist.

drummergirlnancy1 karma

Is medical cannabis contraindicated with dysphagia?

Ethan_Russo3 karma

This is hard to say. Some types of dysphagia (difficulty swallowing) arise due to conditions producing muscle spasm. Certainly, cannabis can help there. Cannabis can be inhaled via vaporizer, bypassing the need to swallow.

Melmab1 karma

Does cannabis help with nerve pain associated with Multiple Sclerosis? Currently having pains I can only compare to getting whacked in the elbow with a baseball bat, and standard pain meds don't do much.

Ethan_Russo4 karma

A study of Sativex (nabiximols) by Rog that is summarized in the book chapter showed good evidence of relief of central neuropathic pain in MS with that preparation (equal THC, CBD plus terpenoids).

Here is the study abstract:

mcgillycuddy4121 karma

Hi there! I have 2 questions, so feel free to answer whatever you'd like!

  • I've seen you mention consistency and quality control in a couple replies, what is your opinion on what the company GrowBlox is doing in that regard? Are they at least on the right track?
  • What role do you think cannabis plays in the progression of Alzheimer's? It certainly has effects on memory, but how can this be beneficial as a medicine?

Ethan_Russo3 karma

Question 1: I cannot/will not comment about specific companies. Question 2: There are therapeutic properties of both THC and CBD that indicate possible benefit in neuroprotection of Alzheimer disease. No formal trials have been done, but in Israel and in Sonoma County, California, populations of people affected have seemingly benefited from such treatment.

Serenitymidwife1 karma

I am wondering about the use of CBD for migraines that are associated with hormonal disturbances primarily estrogen dominance. Marijuana I was under the impression increases estrogen production. If hypothyroid and adrenal insufficiency are present with estrogen dominance would CBD use just cause more problems?

Ethan_Russo2 karma

CBD has not been formally tested in clinical trials, but may prove quite useful. There is no information to support that CBD, or THC causes permanent endocrine abnormalities, although acute changes may be seen

Serenitymidwife1 karma

So acute changes possible. Would these acute changes with a consistent use level out as the body normalizes with the use? And would the use of CBD for the pain relief cause any issues with the Liver metabolism of hormones ?

Ethan_Russo2 karma

Again, all the hormonal flux seems to disappear over time unless there are other factor operative.

spock_bosco1 karma

Dr. Russo, I recently attended a talk by Dr. Martin Lee where he references your and PhyTec's recent research into "naturally occurring" terpene clusters or families. He mentioned that you guys had identified like 18 families of terpenes. Are you prepared to discuss that research in any capacity yet?

Ethan_Russo3 karma

More to come on this later.

420divarx1 karma

THC has significantly improved my gut issues but they've been returning since I added CBD to my ingestible dose. Does the CBD block the GI receptors that THC was activating for me previously?

I've stopped the CBD now to investigate.

Ethan_Russo2 karma

Unfortunate. Trial and error is necessary in cannabis-based medicine, particularly since quality control and consistency are hard to come by in the industry.

RRARyan1 karma

Fibromyalgia, MS, and arthritis are a few examples of chronic pain. Is there a common feature or trait among the various types of chronic pain where cannabis is effective in moderating the pain levels?

Ethan_Russo3 karma

Cannabis is a multi-modality pain reliever. See book chapter on pain:


Has cannabis ever been proven to be a legitimate alternative for treating chronic pain? We hear stories about people using mary j to treat it, but from my impression its that it's a last resort type of thing or for more casual pain relief. I'm curious to whether it has been documented to have greater efficacy in X category compared to modern drugs in the respective category.

Ethan_Russo2 karma

See the pain chapter with Andrea Hohmann in the publication list.

420divarx1 karma

In an attempt to reduce solvents in my medicine.Have you seen any research on solventless/solventfree extracts and cancer?

Ethan_Russo2 karma

Repeating, the safest concentrates of cannabis are hashish, or CO2 or ethanol extracts.

Vladecho1 karma

Hey, hopefully I'm not too late! I've heard that cannabis can help with migraines. My fiancé has migraines all the time, sometimes it is several times a week, and he'll get an occasional cluster headache. Would marijuana actually help him?

Ethan_Russo3 karma

Please take a look at the publication list here:

There are several entries on migraine, especially the Clinical Endocannabinoid Deficiency article. I have an update on that submitted for publication. Cannabis has been one of the most effective treatment for migraine. An observational trial in Colorado was just published:

DriftwoodSeashell1 karma

Living in Vancouver, the product is widely available, and in fact usage is condoned by my pain specialist.
The problem is that what I think we need or I need is a dispensing pharmacist / doctor relationship, where I am not just winging it as far as trying product. I don't like feeling high. I just want to contend with pain with something less toxic than opiates, which I have radically cut down on.
Have had chronic pain for several decades. (DDD, arthritis, cervical neck degeneration issues mostly) Is there anywhere that actually gives that kind of advice, or are we left to research and trial/error? Can you envision something like that happening if it is legalized in Canada? Where you can get advice on your Rx as you would with a prescription drug?

Ethan_Russo2 karma

You need a doctor who is interested in this type of medicine. There are several in the Vancouver area. You may start by asking around or at a Compassion Club.

Sabiduria_CoJo1 karma

Dear Ethan,

What is the most effective way (to get the most bang for your buck so to speak) to take cannabis? Joint, pipe, oil/extract, vaporizer, etc

What is the healthiest way to take cannabis?

Ethan_Russo2 karma

Healthiest is oral or oromucosal administration. Vaporization reduces, but does not eliminate potentially toxic by-products (polyaromatic hydrocarbons, ammonia, etc.).

Sabiduria_CoJo1 karma

I'm not sure if my first two questions ended up posting to the site, I haven't been able to find them on & am new to the site.

Anyways, one of the questions got asked by someone else, which you answered so here is the other question:

There are many parts to the plant, CBD, THC, etc & there are strains that specialize in being low on some of the parts like THC. All the different parts of the plant have different rolls that they play medicinally. Is it better to have a strain that is specializes in having less active parts or is it better to consume all of the plant?

I ask because I have heard that all parts are needed because of the symbiotic relationship, that certain parts are activated by other parts of the plant.

Not sure if that makes any sense.

Ethan_Russo2 karma

The cannabinoids and terpenoids are concentrated in the unfertilized female flowering tops. There are far less and of different composition in the leaves. The roots have totally different components, triterpenoids and even alkaloids.

Remembering_breath1 karma

Hi Ethan,

Do methods of consumption effect the way that Cannabinoids are absorbed or just where in the body they are absorbed?

A follow-up, I was wondering if you could speak to your knowledge of an studies that have used cannabis oils?

Ethan_Russo2 karma

Yes, delivery techniques markedly affect the pharmacokinetics of cannabis. Inhalation is rapid, but also causes a peak high that is not necessary to most medical usages. Oral intake is a lot slower, but longer lasting. Oromucosal administration is intermediate. Cannabis oils are addressed elsewhere on this page.

thorshairbrush1 karma

What are some dangers of prolonged frequent marijuana use? Ive been smoking almost every day since I was 15 and Im 21 now. Im sure that using any substance for that long has to have affects on me.

Ethan_Russo3 karma

If smoked, daily cannabis usage causes cough, phlegm and bronchitic symptoms with more frequent upper respiratory infections. Excessive use can affect some cognitive functions, but often people develop tolerance to the psychoactive effects.

Redici1 karma

Hey, sorry if I'm late. I have seen multiple places (mostly reddit) that cannabis could lead to short term memory loss and a couple other "memory loss" type thing but that it's also a powerful study tool. So is there any known link to memory loss because of cannabis?

Ethan_Russo2 karma

Many. Look for studies by Pope and Grant on the PubMed website, and also the older review in the Chronic Use Study in the publication list.

legolana1 karma

Hi! I'm starting college in the fall with a major in neurobiology and physiology. Hoping to become a neurologist. Any advice? Thanks for doing this!

Ethan_Russo2 karma

Study hard and study long. Don't forget to have a good time.

pakage1 karma

Is juicing Marijuana an effective way to ingest CBDs? Also, is there enough CBD in hemp to make it a worth while (juicing) alternative for medical marijuana in countries where hemp growing is legal but marijuana is not?

Ethan_Russo3 karma

CBD is one thing, cannabidiol. When juicing cannabis, there is actually little or none. Rather, what might be present are tetrahydrocannabinolic acid and cannabidiolic acid. There have different effects. Once people start trying to extract hemp, new rules apply, and the practice is still technically illegal in many jurisdictions.

KatyDid7491 karma

Any use for it in treatment of macular generation? I am 41 and was recently diagnosed. To young, blah blah it stinks.

Ethan_Russo2 karma

Perhaps, but this has not been formally studied as yet.

BoringBostonQuestion1 karma


I am interested in cannabis for the health benefits and ONLY the health benefits. I do not want to get high.

Are there any derivatives of cannabis that can meet my needs?

Ethan_Russo1 karma

A person with these aims would do well to look for CBD-predominant strains with as little THC as possible.

Remembering_breath1 karma

A few questions. Please answer as many as you would like.

I work in the cannabis industry in a dispensary in BC. I do a lot of self-education of the effects of cannabis. Sadly the current political spectrum, specifically in Canada is that research is limited and conclusion on the effects of cannabis cannot be made or are limited. Though I understand the concept that research and specifically statistics is building on rumble and based on the inaccuracies of human error and interpretation of the raw data. The culmination of scientific results provides strong evidence based on small sample repetition. My questions are regarding research reliability.

  1. With all of your skills and experience what made you decide to work for GW Pharmaceuticals?
  2. With the work that you did while with GW Pharma was the research funded only by the company? and if so how can you justify any results based on the bias in funding?

Ethan_Russo2 karma

I am not going to get into politics. I worked with GW because it was a necessity as the only way to do clinical cannabis research, as that path was blocked and remains so to a great degree in the USA. Additionally, I felt strongly that the company was pursuing good work to help patients. I continued to do research on my own as best possible and that remains true today.

imasensation1 karma

Hi. I have used marijuana, as well as cannabis oil for about 6 years straight with a total of about 3 months off throughout that time. Are there any questions you have for me about anything? I smoke and am under the influence at every waking hour of my day (I switched to cannabis oil over the last year).

Ethan_Russo1 karma

The switch to oil certainly suggests the development of tolerance. This is not a permanent condition, however, and periods of abstinence ("drug holidays") are one approach to that. It would be worthwhile to examine your reasons for using cannabis with this frequency and this level of dosing. See Dustin Sulak's comments in this article:

CrumpetRocket1 karma

How do you feel about the abuse of marijuana as medicine? ("My eye itches") Do you think it has degraded the general public's opinion of its legitimacy?

Ethan_Russo1 karma

In brief, people should use cannabis as medicine according to need. There will always be some "gaming" the system, but those who require it should not suffer for their misdeeds.

sanyc1 karma

Can Pot be addictive? I know a guy who's friends with a guy who can't quit.

He says things like "This is the last time" or "next week I'm done", but never actually quits. Meanwhile, his life is slowly draining into the gutter. Is there any evidence that pot can be chemically addictive like heroin/ nicotine, or is it purely behavioural?

Ethan_Russo1 karma

See responses elsewhere on the page.

shoneone1 karma

Could cannabis use precipitate Parkinson's? I am a long time cannabis micro-doser and have developed parkinsonian tremors. I find smoking cannabis is a stimulant and sometimes makes me hyper aware and jittery, so the connection seems plausible. I also worry about loss of cognitive capacity, which could be Parkinson's or could be cannabis use. Your comments are greatly appreciated!

Ethan_Russo2 karma

Not likely related. Unfortunately, Parkinson disease is actually a syndrome of many causes: age, genetics, vascular damage, toxins, etc. Whatever causes loss of 90% or more of cells in the substantia nigra will precipitate its expression.

internetversionofme1 karma

Super late, but I'm hoping you check back and see this. What is your stance on cannabis use for mental illness, specifically anxiety? My anxiety can be pretty crippling at times, and I find that smoking occasionally (while I'm careful not to use it as a crutch) greatly helps with this for me. At the same time, however, I worry about it negatively affecting my depression.

Also, is there any research to your knowledge on the development of psych meds from cannabis?

Thank you for the AMA. I found it to be a very informative and enjoyable read!

Ethan_Russo2 karma

See responses elsewhere, especially with respect to cannabidiol. It is of proven benefit in social anxiety. This area is deserving of more research and funding, but few companies seem interested in its pursuit.

Rapidshotz1 karma

Cannabis Vs. Muscle relaxers/tramadol etc., what is your take on choosing which substance would be better usage long term for chronic pain/arthritis?

Ethan_Russo1 karma

Cannabis contains compounds that help muscle spasm (THC) and pain (THC, CBD) and inflammation (CBD>THC). Cannabis, when properly used has a safety profile equal to or better than most applicable pharmaceuticals, but quality control is lacking on the black market, and there is always the legal jeopardy angle.

sergio21021 karma

Hi Ethan, I have a question about short-term memory. I read a lot of literature, articles and wrote some essays on how cannabis influences our bodies. About memory, it is quite vague to me what happens to short-term memory and if anything negative happens, will the memory recover after some period of time. Also, if I may ask, do you think cannabis will be legalised in the future all over the world and what are the main reasons governments are not legalising it now? Thank you.

Ethan_Russo2 karma

See responses elsewhere. In brief, STM impairment is associated with THC, but can be alleviated by alpha-pinene, if available, in a particular cannabis strain. The memory problems seem to be alleviated after chronic use once a person is abstinent for a month.

LedZeddelin1 karma

Hello Dr. Russo,

I recently read your paper "Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects."

I have two questions:

1) This paper was published in 2011, do you plan on updating these finding anytime soon? Are there any new synergistic relationships to report?

2) Limonene is one of my favorite terpenes, taste and smell wise, I recently heard that this terpene causes one to become energetic, have you heard anything to support or deny this claim?

Thank you for doing this AMA and for doing the work that you do. You are a total rock star in my eyes - except instead of trashing hotel rooms you are compiling research that could help millions. So once again THANK YOU.

Ethan_Russo1 karma

I'd love to say that there is a lot more to report, and there may be in the future, but that depends on obtaining funding for expensive studies to prove the concepts and theories in the article. Many people find limonene in their cannabis to increase energy, while others find it peaceful or antidepressant.

baconsandwichfaggot-1 karma

What is the medicinal explanation for the correlation of marijuana comsuption and hacky sack playing?

Ethan_Russo6 karma

We're here today to discuss medicinal use of cannabis, not add to the giggle factor.

RRARyan1 karma

Ethan, To start, what are the major types of chronic pain?

Ethan_Russo2 karma

neuropathic cancer bone nociceptive inflammatory

TrishFlaster1 karma

What forms , cultivars or cannbinoids are helpful for sciatica pain

Ethan_Russo3 karma

This is a tough one. In the 19th century, benefit was noted with what we assume were high-THC strains. Some early work with Sativex (nabiximols) looked at patients with such problems and this 1:1 THC:CBD mixture in low doses regularly seemed the most promising.