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Cannabidiol (CBD) — what we know and what we don’t

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August 24, 2018

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Comments

Jo Bowen
October 17, 2018

Should one take as gospel the equivalencies between CBD and Grapefruit juice? Eg, if grapefruit juice affects the metabolism of Omeprazole and I am taking Omeprazole, should I avoid adding CBD to the mix?

Peter Grinspoon, MD
October 19, 2018

Nothing about CBD is “gospel” yet; much more studies need to be done. Omeprazole is pretty safe, by and large; I think the biggest concern with CBD would be with medications where an altered, irregular dosage could be dangerous, such as blood thinners…

Hank Waterman
October 17, 2018

I suffered two concussions within a space of 7 weeks: once after falling on ice, and once in a traffic accident. That was about 18 months ago and I still suffer from post-concussion syndrome, which is barely tolerable. Hyper-sensitivity to light and sound, exhaustion, some dizziness, some cognitive impairment.

I hesitate to try anything that might further impair my cognitive function but I am willing to give cannabis a try (now that it is legal in Canada).

Is there any good research on the effects of cannabis on a concussed brain?

Thanks
Hank Waterman

Peter Grinspoon, MD
October 17, 2018

There is some evidence that cannabis is neuroprotective, and can help protect against Traumatic Brain Injury:
https://www.ncbi.nlm.nih.gov/pubmed/25264643
This needs to be studied more!

Tressa Molloy
October 05, 2018

I’ve been fighting chronic pain for over 35 years. It’s like being in prison. I just started cbd oil and want to learn everything I can about it. My only hope.

Peter Grinspoon, MD
October 08, 2018

I hope it helps. Good luck!

Tim Andersen
September 29, 2018

I need some clarification here. How can CBD be “derived” from the hemp plant, when the Marijuana already contains CBD? Furthermore the hemp plant and the marijuana plant, is the “same” plant, in that “hemp” is the male version, Marijuana is “female” version.
Or would you say I’m wrong in this assumption?

On another note, CBD helps PREVENT nausea, fatique and irritability. It’s not some side-effect of it?

I’m not at all an expert, so I will not act like I know it all, and you are just wrong. However, I do want to know,what you base these claims on?

Peter Grinspoon, MD
October 01, 2018

Thank you for your questions. Marijuana and hemp are two extremely different strains of the same cannabis sativa plant that have been bred over thousands of years to have entirely different purposes. (Hemp is not the male version of the marijuana plant.) They both contain CBD. Hemp only contains CBD whereas marijuana contains CBD and perhaps a hundred or so other chemicals with a variety of functions, such as THC, the molecule that makes people “high”. Any medicine can have different effects on different people. For example, Benadryl makes some people sleepy yet can make others wide-awake. So, it is not inconsistent for a particular medicine to cause a symptom in one person and to help alleviate it in another. So while many people experience relaxation with CBD, so people do experience the “paradoxical” effect of irritability.

Sen. Connie Johnson
September 23, 2018

I can concur based on real time experience with my Mother who is bed bound with an irreparable fracture to her hip prosthesis. We have reduced her morphine/opioid meds substantially using high CBD and high THC versions. 2x/day. She also eats gluten free muffins containing the oil. She thoroughly enjoys her alternatives and requests them regularly.

Peter Grinspoon, MD
September 24, 2018

Thank you for your comment. It is fantastic that she is able to reduce her use of opioids. This is much safer, and makes for a better quality of life, and I’m sure you are seeing!

Dr. Rachna Patel
September 11, 2018

@Shelley Latin I’m a physician who has treated patients with both hemp & cannabis based CBD. And, what you’re saying is in concurrence with the clinical outcomes I’ve seen in my practice.

1. For certain conditions, such as Shingles and Spinal Stenosis, some amount of THC is needed to effectively relieve the pain. CBD, on it’s own, doesn’t cut it.

2. In regards to CBD eliminating pain, it depends on what level of pain the patient starts with. If the patient starts with mild to moderate levels of pain, then, it’s certainly possible to eliminate the pain. But, if the patient starts with severe pain, then it’s less likey, I’d say.

3. In the best case scenarios, my patients have completely eliminated the use of opioids and just use CBD on an as needed basis to manage their pain.

Hope that helps.

With Gratitude,
Dr. Patel

Peter Grinspoon, MD
September 11, 2018

Very helpful! Thank you for your thoughts. Absolutely consistent with what I’m seeing in clinic as well.

Jason
October 02, 2018

Cannabidiol may partially normalize alterations in parahippocampal, striatal, and midbrain function associated with the CHR state. As these regions are critical to the pathophysiology of psychosis, the influence of CBD at these sites could underlie its therapeutic effects on psychotic symptoms.

https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2697762

Dr Glenda (surname withheld due to fear)
September 07, 2018

Thank you. I am 81 and started the CBD drops night and morning. I sleep better and no longer suffer the excruciating pain from diverticulitis. I saw somewhere that for my asthma I need the THC so got some (totally illegal here in South Africa). I think it is helping. The diagnosis of COPD was made some years ago and as a health psychologist I do all I can to remain healthy for my 97th birthday!! (Both my grandmother and greatgrandmother did so I believe I will too).

Peter Grinspoon, MD
September 07, 2018

Thank you for sharing your experiences. Happy 97th birthday in advance!

Justin Kenp
September 07, 2018

Great Stuff.. It seems, you have researched a lot before posting the blog. Thank you for sharing such a important information, as rarely people know this use of CBD. I know about CBD but not aware the CBD can be use in this way as well.

Peter Grinspoon, MD
September 07, 2018

Thank you for your comments!

Shelley Latin
September 05, 2018

I have read about studies from Europe (not very specific I know) that suggest CBD might work better for some people if combined with some level of THC. Also, the getting high part can be helpful, although not for everybody, of course. A second point – I don’t hear very much about CBD eliminating or almost eliminating pain for people with severe pain. Helpful, but, so far at least, it doesn’t seem that CBDs can replace opioids or substantially reduce pain for all chronic pain patients. Maybe someday.

Peter Grinspoon, MD
September 07, 2018

To my understanding, neither CBD nor THC are effective for “severe” pain; rather, they work better for mild to moderate chronic pain. Often, with severe pain, the dosage of opiates can be decreased with concomitant use of medical cannabis or CBD and that decrease in dose makes their use safer. Concurrent use of THC does increase the analgesic effect of CBD, but it also adds the “high” which some people do not want as a side effect.

Peter Grinspoon, MD
September 04, 2018

It is definitely a problem with all nutritional medications and supplements — they aren’t rigorously regulated and it’s difficult to know what dosage you are actually getting. I wish they were far better regulated, both in terms of dose and quality, and in terms of the claims they are allowed to make…

Peter Grinspoon, MD
September 04, 2018

That is an unfortunate situation; you can find another hospital system, advocate for change within that hospital system, or you can educate. yourself about this issue and try these medications on your own (which is what a lot of patients end up doing unfortunately…).

Peter Grinspoon, MD
September 04, 2018

It can raise you levels of blood thinners and, as such, the levels should be monitored more closely when you start using CBD, but it can’t replace the need for blood thinners.

Peter Grinspoon, MD
September 04, 2018

CBD and THC interact competitively at the receptor level, so it is true that CBD can lessen the “high” that THC causes.

Peter Grinspoon, MD
September 04, 2018

Thank you for sharing your experiences with CBD.

Peter Grinspoon, MD
September 04, 2018

Yes, Hemp-derived CBD has no THC and is less likely to have side effects but some people claim that, for this exact reason, it has less efficacy.

Chris M
September 02, 2018

There are hundreds of chemicals found in both Hemp and Cannabis. CBD is only one noteworthy analyte. CBD likely acts as an antagonist to THC and will likely reduce the euphoric properties of THC. THC has very important therapeutic effects that are both noteworthy and novel as well.

Unfortunately due to the disappointing and down right inaccurate position of the federal government in classifying Cannabis as a schedule one drug, most research institutions risk federal funding if they conduct real research on Cannabis. This has dramatically limited the potential for real research by real scientists to be conducted. That research is critical to better understanding the multitude of therapeutic effects of the various chemical constituents found in Cannabis.

Because of the vast diversity of chemicals found in Cannabis(THC, CBD, CBN, CBG, etc) isolating a specific chemical can paint an inaccurate picture of the medical efficacy of plant. In fact, Dronabinol(synthetic THC), as an example, has turned out to be a pretty dangerous drug.

Although I’m no physician, and am not qualified to recommend any drugs for any specific medical purposes, and you should consult your doctor when considering the consumption of anything that may be medicinal: If you’re looking to experiment with CBD products, you might consider looking for CBD products that are “whole plant” extract based from very high CBD cultivars. If you’re in a State that has a legal Cannabis system, you may also find more therapeutic benefits from non-hemp derived CBD products.

There is quite a bit of NIH data available on CBD, and other chemicals found in Cannabis:

https://www.ncbi.nlm.nih.gov/pmc/?term=CBD

There are likely very complex relationships also occurring between various Cannabinoids in Cannabis that may lead to certain medical efficacy. That is important to remember when considering the consumption of products that contain Cannabinoids. There is an attractiveness to isolating a specific chemical, researching it, patenting synthetic derivatives, and marketing specific drugs. That said, the relationships are complex, will likely take years to understand, and many patients I’ve met appear to find the most medical benefit from a diverse group of Cannabinoids whose interactions are not particularly well understand, but the results are hard to argue with.

Dolores Hark
September 01, 2018

I use this for my anxiety and for my arthritis. The topical works great for my chronic neck pain. The best way to go is to get your own raw, tested material and use it in whatever form you like. It’s quite easy to make your own extract. This has worked better for me, rather than relying on a purchased, untested product – where some seem to work and others are a waste. But even with those that work, of course the cost is ridiculous and not affordable, thanks to all these corporate-pleasing laws in place, not there for the people – don’t delude yourselves.

A few years back I recall unethical big pharma trying to stick a patent on the CBD extraction progress. Now I am not surprised they take this natural healing substance and stick it in a pill form – annoying US medical industry.

Also to my understanding it is already now legally to grow industrial hemp in all 50 states from which the more pure CBD products are derived.

It makes no sense to me that something that helps with anxiety has an irritability side effect – as a lot of my anxiety is co-mingled naturally with irritability. Further, I have noticed none of these side effects, given that if you become fatigued or sleepy, you adjust dose the next day. So I don’t call that a side effect – rather – an effect of taking too much.

But let’s face it. This is all a great disgrace that any of this is illegal and is simply an artifact of our corrupt, corporate-driven political system, still in place to this day.

I am laughing at the annoying pharma industry – it’s the pills that are killing us, not the weeds. SHAME on anyone who participates in this corrupt medical system and shames people for wanting their rights back to nature.

Susan Hancock
September 01, 2018

Sub-lingual CBD drops have helped me enormously with sleeping and with radiation damage pain. I have a cancer that spread from the pelvic area to my sacrum and sciatic nerve and whilst the chemo and radiotherapy saved my life I have been taking MST (morphine derivative) for nerve pain ever since. My tumours are presently all quiet and last March I decided I wanted to stop taking the pain relief drugs, fearing dementia. CBD oil was recommended by my son who has arthritis and, for me, it really works. It’s so good to read an article that isn’t put out by a CBD sales site – I wish it could be properly prescribed and regulated (I’m in the UK) in order to have confidence with purity and dosage.

Kevin Smith
August 31, 2018

Great article, except that clarification is needed regarding (potential) side-effects.
From what I understand, CBD derived from the hemp plant does not have the side effects mentioned above, other than possibly to help reduce the amount of Coumadin/Warfarin needed – either way, a patient on this drug needs to be monitored and regularly tested anyway with their doctor. CBD derived from the marijuana plant (will contain THC) may have them, I do not know, maybe that’s why you mention them. One of the many reasons people take Hemp CBD is that it does NOT have the side effects! People take the Hemp version to help with feelings of fatigue, irritability & anxiousness, it does cause it! It helps to bring the body into balance.

Beverly Wilkerson
August 27, 2018

Consumer Reports recently did Some testing on CBD, They only showed 6 with results of their testing. You might want to look it up.

Geoff in NJ
August 27, 2018

So what are my choices if my doctor (and all the others in her practice) are prohibited by their hospital corporation from assisting patients figure out whether it just might work?

Jami Vaughan
August 27, 2018

I would love further information regarding the blood thinner/coumadin reaction. I’m interested in trying to get off blood thinners from the western world as a potential bleeding issue later in life. (Gastric ulcers/varices caused by blood thinners).

I’ve been on Warfarin 14 years already due to Ischemic stroke, I’m under 40.

Robert Kauai
August 26, 2018

I recently was a guest at a medical marijuana educational event that highlighted the work of researcher Michael Backes. During his presentation he made a statement about CBD that I have never heard anywhere else that CBD is “regulating” (my word) the effects of THC. I asked the Nurse Practitioner at the event, Ivy Lou Hibbitt of Certicann.com, what he meant by that and she said it was her understanding of Michael’s comment that he takes CBD to reduce the psychoactive effects of THC. Has this property of CBD, that it can lessen psychoactive effects, ever been researched elsewhere?

Kim
August 26, 2018

CBD has been able to erase my permanent nerve damaged pain in my left leg. Previously only Fentanyl did that. However, neither one has helped my chronic back pain. Ice and pain meds helps my back pain although I feel like I’m treating like a drug addict to get my very needed Tylenol 4-3times a day only. Thanks, Kim

Carrie
August 25, 2018

Great article, except that clarification is needed regarding (potential) side-effects.
From what I understand, CBD derived from the hemp plant does not have the side effects mentioned above, other than possibly to help reduce the amount of Coumadin/Warfarin needed – either way, a patient on this drug needs to be monitored and regularly tested anyway with their doctor. CBD derived from the marijuana plant (will contain THC) may have them, I do not know, maybe that’s why you mention them. One of the many reasons people take Hemp CBD is that it does NOT have the side effects! People take the Hemp version to help with feelings of fatigue, irritability & anxiousness, it does cause it! It helps to bring the body into balance.

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