Talk:Cannabis (drug)

NPOV??

While there is some phrasing issues I don't see how this article presents a non neutral point of view. The only thing wikipedia can do about a subject such as this is describe the drug as it stands is society which this article does. However some will never accept this goal. Presenting a non neutral point of view is not difficult there are just too many opinions on this subject to generate a legitimate article free from tags of bias and assertions of other problems.— Preceding unsigned comment added by 75.128.153.150 (talk • contribs) 04:46, 25 May 2011 (UTC)

Safety section: coming to a resolution

We have this section tagged, and still the unresolved RfC about what good science says regarding cannabis and its effects on the heart remains. Can we bring this to a closure? If editors involved could please look over the safety section, and any problems you see, bring it here for discussion, that would help. Then we can be reasonably sure once we've reached consensus, this section should remain fairly stable and we can get back to our other work. In other words, we shouldn't expect to walk away and then have presently active editors removing agreed-upon bits from this section (in a perfect world, that is).

The issues I have with the safety section are:

• The science and understanding Nbauman offered should be swapped with what we have now regarding cannabis and cardiovascular effects (which seems to say that science shows cannabis causes heart attacks, and which uses lower quality sourcing).
• The DEA Judge's statements should be re-entered (I've already argued both points on this page). petrarchan47tc 04:50, 4 February 2013 (UTC)

We have previously mentioned a formal process of dispute resolution. I still believe that is our best option after all this nonproductive dispute. Having a formal neutral process seems to be the best bet of hearing positions from all interested parties and coming to a resolution. I can start the process within a day. Rlsheehan (talk) 08:29, 4 February 2013 (UTC)

Rlsheehan, I see that you have not mentioned your problem with Dr Lester Grinspoon's statement which you removed yesterday. Please, if you have concerns with anything in the safety section, bring it up now so that we can look at it as a group, rather than when no one's looking. Thanks. petrarchan47tc 00:42, 5 February 2013 (UTC)

I've asked the other involved editors to weigh in here too. petrarchan47tc 08:44, 4 February 2013 (UTC)

My position on DEA judge comment has not changed. It should not be included for the reason I've already given. Cantaloupe2 (talk) 09:01, 5 February 2013 (UTC)

Thanks Petrarchan for calling me.

• N I don't understand what "science and understanding" Nbauman offered. We have a clear-cut secondary peer-reviewed medical review that says things clearly on marijuana cardiovascular effects. I see nothing of similar quality from his part: he offered a primary source that also cited a secondary source on marijuana: if anything ,we should directly cite that one. The rest he offers is clearly original research. By the way, there is a nonsense OR tag in the current version (and I'm going to remove it): it is nonsense since the sentence is as 1:1 to the source as it can without introducing copyvios. The "contradiction" that some editors see does not really exist. Saying that something is generally safe is not the same to say that it never has side-effects, and saying that no death has been directly caused by marijuana doesn't mean deaths can't be linked to marijuana use as a concomitant factor, for example. If there are directly conflicting reports, then we ought report that there are conflicting reports in the literature, and that's it.

• N I still think we must not include any quote of any single individual, whatever it says, and especially not a quote from a non-medical specialist. That can easily be construed as cherrypicking (and indeed IMHO it is, regardless of the fact that I personally largely agree with the quotes).

There are serious NPOV problems here, if not much in article content, more in attitude. While the POV being pushed is basically scientific consensus, and as such it's mostly okay, the fact that editors are squirming to remove any mention of scientific sources that cast even remote doubts on the safety of marijuana (while the samesources, indeed, state that marijuana is safe in general, so that's even more ridicolous) is a problem. Nbauman and Petrarchan47 seem hell-bent on removing every reference on even the remote possibility that for some people, in some rare cases, marijuana can have side effects. (I remember when Petrarchan said: "Because still this article remains the only place one will find mention of cannabis deaths, unless they stumble across this or the 2 articles that cite it. " - if this isn't explicit cover up, I don't know what it is).

If this is not settled quickly, I would:

• • go on RS/N to clarify the status of the review about cardiovascular effects of marijuana
  • open a whole new RFC on that source and its inclusion.

Hope it helps. --Cyclopia^talk 15:57, 4 February 2013 (UTC)

OK. My position is that The Journal of Clinical Pharmacology is not a major medical journal, but I agree that the International Journal of Cardiology is -- and the authors are from Massachusetts General Hospital, which gives them more authority. I checked and I have access to IJC, and I just downloaded a PDF of the full article. If anyone needs a copy, I can email it to you. I have to read the full article, but here's the conclusions. I have to go with the medical evidence. There does seem to be fair evidence that marijuana sometimes is a trigger for MI.

4. Conclusions

Marijuana use by older people, particularly those with some degree of coronary artery or cerebrovascular disease, poses greater risks due to the resulting increase in catecholamines, cardiac workload, and carboxyhemoglobin levels, and concurrent episodes of profound postural hypotension. Indeed, marijuana may be a much more common cause of myocardial infarction than is generally recognized. In day-to-day practice, a history of marijuana use is often not sought by many practitioners, and even when sought, the patient's response is not always truthful. Thus, clinicians should be more vigilant in inquiring about use of marijuana in their patients, particularly among the younger adults who may present with cardiac events in the absence of cardiovascular disease or other obvious risk factors.

[Future areas of research]

My problem is that I don't want to exaggerate the strength of the evidence. These seem to be uncontrolled case series Evidence-based_medicine#Assessing_the_quality_of_evidence, AHA which is a relatively weak level of evidence. Doctors would normally not recommend a treatment based on uncontrolled case series (unless the risks of treatment are very low and the benefits very high).

I'm trying to figure out a way to say that without violating WP:OR. There may be something in the full IJC article.

I'd like to find a statement like that in a major medical journal, and the NEJM came close.

I think Young's statement is a WP:RS and would provide adequate balance,

My problem, to put it another way, is that there is evidence that marijuana causes MIs, but it's weak evidence. It's supported by the scientific literature, but there's very little literature. (I could only find one good source.) I heard academic doctors (like Donald Abrams) say in a lecture that there's a bias in the funding sources against anything that could be favorable to marijuana (and indeed federal law says that).

My problem is that I don't want WP to make a stronger (or weaker) statement than than is justified by the literature. The literature -- that is, the one article in IJC -- doesn't just say "linked" and "associated", it says "cause." I'm willing to paraphrase the claim from IJC that marijuana "may be a cause" of MI, or maybe even that it "may be a common cause" of MI, provided that we also say that it was based on uncontrolled case studies and link to the Evidence-based medicine article. I also want to read that IJC article and see whether their cases are of people with pre-existing cardiovascular disease or of young people with no risk factors. If the IJC article says that these were MIs, but not deaths, we should make it clear that these were not deaths.

If I had a friend with cardiovascular disease, and he asked me whether it was safe for him to smoke marijuana, I'd tell him that there were rare cases in which it precipitated a heart attack, and it had the same kind of risks as he would have shoveling snow. That's what I'd like to convey in the article, in a way that avoids WP:OR. --Nbauman (talk) 19:36, 4 February 2013 (UTC)

I just looked at the article cited in the NEJM. This is a case-control study in Circulation, which I have to admit is stronger evidence. I'll have to read the full article (which is free text) before I come to any final conclusions.

Triggering myocardial infarction by marijuana. Mittleman MA, Lewis RA, Maclure M, Sherwood JB, Muller JE. Circulation 2001;103:2805-2809 --Nbauman (talk) 20:02, 4 February 2013 (UTC)

Most of these articles use the word "trigger" than a stronger "cause" relationship. I recommend that this Wikipedia article mention a link to occasional MI or stroke as we were previously discussing. More could be located in the Effects of cannabis article in the Short Term, Cardiovascular section. I have already attempted to add some of this discussion there. Rlsheehan (talk) 20:25, 4 February 2013 (UTC)

Nbauman: "there is evidence that marijuana causes MIs, but it's weak evidence." - Then let's just write that. Something like in the medical literature there are only a few reports linking cannabis to MIs. --Cyclopia^talk 22:48, 4 February 2013 (UTC)

I don't count the number of times a term is mentioned in the journals. I weigh the major journals more heavily than minor journals.

2 articles in major cardiology journals used the term "cause." That should be enough to use the term "cause." We could also mention "trigger." But the issue is causality.

"Linking" is not a precise term. What does it mean? Coffee was linked to heart attacks. That's because people who drank coffee were more likely to smoke cigarettes. Coffee didn't cause heart attacks.

The issue is not whether there are a "few" reports. The issue is whether there are studies that establish cause with scientific validity. There are, but the evidence is weak (and the magnitude of the effect may be small). But we can't say that without a WP:RS. We can say that they are case-control studies, and link to the discussion of case-controlled studies in Evidence-based medicine. I think we should. --Nbauman (talk) 00:06, 5 February 2013 (UTC)

Nbauman, if we were talking in a pub or at a scientific conference, I'd agree. But here it is different. We're not here to second-guess sources. "2 articles in major cardiology journals used the term "cause." That should be enough to use the term "cause."" - And in fact, yes it is. Even if I agree with all your doubts: if sources do, we ought to use that term. The issue is causality? Excellent: debate it in the academia. On Wikipedia, if sources say something, we repeat what they say, we don't do original research. That said, I agree with your last 2 sentences. --Cyclopia^talk 00:12, 5 February 2013 (UTC)

(Reply to first comments by Cyclopia) I am not hell-bent on removing anything unless it fails to meet RS. My recent removal of the line about CBD was because it's too problematic to try and equate CBD with cannabis. Few have yet heard of CBD, so to mention related "side effects" when they aren't specified in the article or found in the single in-vitro study referenced added little clarity to the section. (The only side effects from CBD of which I am aware are all extremely positive.) The CBD information could be explored in another section or article, but I don't think this one is the place for it. IF i were hell bent on removing anything about cardiovascular effects I would have done so, just as others have removed the DEA Judge and Lester Grinspoon's comments. Instead, I simply tagged it WP:OR. I truly want to report whatever good science is saying, but it needs to be presented accurately and thus far has not been. It's interesting you have no grief with the editors who actually claimed cannabis killed people - that's the POV I am worried about. Yes, this is the only page that claimed cannabis has killed people other than the cherry-picked studies - which means that they aren't being cited and therefore should not be here - unless they are presented in context, as you all are discussing. This is far from a "cover-up" - it's the proper application of Wiki guidelines to not present fringe as well established fact. If there is no science supporting "cannabis has killed people", then anyone who cares about Wikipedia and RS should be thanking me for putting an end to that ridiculous unsupported claim once housed here. Instead I'm the bad guy? petrarchan47tc 01:34, 5 February 2013 (UTC)

• "Instead, I simply tagged it WP:OR." - Which makes even less sense. It surely isn't original research -it's sourced 1:1 to the abstract of a medical literature review!
• "I truly want to report whatever good science is saying, but it needs to be presented accurately and thus far has not been." - Why?
• "It's interesting you have no grief with the editors who actually claimed cannabis killed people" - Because that's what sources say. No matter how it runs against my deeply ingrained point of view about it, no matter how much it surprised me, it's not kook pseudoscience, it happens to be reported as a rare side-effect in a few authoritative medical reports. As such, it is worth mentioning. I mean, let's talk straight. Me and you agree, on a personal, POV level, that cannabis should be legalized, for example, and that it is basically extremly safe. This doesn't mean it cannot have some rare side effect, does it? Even drinking water can have serious side effects, this doesn't mean water isn't safe in general.
• "Yes, this is the only page that claimed cannabis has killed people other than the cherry-picked studies - which means that they aren't being cited and therefore should not be here" - This is nonsense. First of all, AFAIK, none of our WP:RS policies require that studies have to be widely cited to be considered reliable sources (even if for sure a widely cited source could be more authoritative, in some contexts). Second, it is false. Actually the review linked now in the section is widely cited in the medical literature, with >100 citations. (cfr. Google Scholar citation list for the paper -which by the way is a treasure trove of good papers on cardiovascular effects of marijuana, see for example [1].) The single study that triggered the first RfC is cited about 80 times, still according to Gscholar. Granted, Gscholar counts tends to err on the excess side, but even if only 50% of citations are genuine (usually it's more 75-85%, judging from citations of my own papers), it still would be respectably cited.
• "If there is no science supporting "cannabis has killed people"" - But there is, if not supporting it, at least suggesting it. No matter how uncomfortable we can be with this, we ought to report it. It's not a fringe theory: it's perhaps a minority position, but there are data, it's in the biomedical literature and, as shown above, cited by the medical community. Such stuff is mentioned in science articles. --Cyclopia^talk 11:12, 5 February 2013 (UTC)

i see great progress here. It sounds like we will be able to get a consensus very soon. One other problem I see in the Safety section is the current; "Dr. Lester Grinspoon, Associate Professor Emeritus of Psychiatry at Harvard Medical School and author of Marijuana, the Forbidden Medicine says that one day cannabis "will be seen as a wonder drug, as was penicillin in the 1940s. Like penicillin, herbal marijuana is remarkably nontoxic". Yes, the professor has credentials but the quote is from an Opinion page in a newspaper. That does not make the cut for a good medical source. A peer reviewed journal article would be good. Rlsheehan (talk) 02:11, 5 February 2013 (UTC)

Untrue, if the person is a recognize expert in the field, RS in and of themselves, you can reference even their own blog on Wikipedia. Yes, this article is RS and Grinspoon's findings after 30 years researching at Harvard is very worthy of our article. petrarchan47tc 00:45, 6 February 2013 (UTC)

According to WP:RSOPINION. it must clearly be described as an Opinion. the present wording does not do this. Rlsheehan (talk) 03:50, 6 February 2013 (UTC)

According to RSOPINION: "Some sources may be considered reliable for statements as to their author's opinion, but not for statements asserted as fact without an inline qualifier like "(Author) says...".... explicitly attribute such material in the text to the author to make it clear to the reader that they are reading an opinion."

Here is the present wording: " Dr. Lester Grinspoon.... says that one day cannabis... " - I fail to see the problem. petrarchan47tc 09:16, 6 February 2013 (UTC)

Cyclopia, if editors agree that the references you're wanting to cite say "if not supporting it, at least suggesting it" then let's say that. I am happy for this article to reflect the science - I just don't believe we have agreed on what should be used, and what exactly it says. The science doesn't say cannabis has killed anyone, is that right? Remember WP:TECHNICAL that we need to write highly technical section 'one level down'. The article is NOT clear about this and I guess that's a reflection of the editors' collective lack of clarity. The editors here have yet to agree on what references to use, and what they say. This is a controversial, for some emotional, subject. It may require another type of noticeboard. petrarchan47tc 00:45, 6 February 2013 (UTC)

Another source to settle this all?

Okay, now I'm looking at this, which is a review from The Lancet, possibly the most authoritative medical journal (I think Nbauman will agree on this). It is from 2009, and as such it supersedes the analogous 1998 review in The Lancet cited now in the article. It also cites directly the review discussed above (ref.56). I am in my university office and I can access full text. Here are a few quotes on side effects and risk of death:

• General side effects: "The most probable adverse effects include a dependence syndrome, increased risk of motor vehicle crashes, impaired respiratory function, cardiovascular disease, and adverse effects of regular use on adolescent psychosocial development and mental health." (abstract)
• Risk of vehicle accidents: "Gerberich and colleagues20 found that cannabis users had higher rates of hospital admission for injury from all causes than had former cannabis users or non-users in a group of 64 657 patients from a health maintenance organisation. The risk of motor vehicle accidents (relative risk 1·96) persisted after statistical adjustment in men. Mura and colleagues21 showed a similar relation in a study of THC in the serum of 900 individuals admitted to a French hospital for motor vehicle injuries and 900 age-matched and sex-matched controls. Drummer and colleagues,22 who assessed THC in the blood in 1420 Australian drivers killed in accidents, showed that cannabis users were more likely to be culpable than were non-users (odds ratio [OR] 2·5). Individuals with blood THC concentrations greater than 5 μg/mL had a higher accident risk (OR 6·6) than those without THC. Laumon and colleagues23 compared blood THC concentrations in 6766 culpable and 3006 non-culpable drivers in France between October, 2001, and September, 2003. The investigators showed increased culpability in drivers with THC concentrations of more than 1 μg/mL (OR 2·87). A dose–response relation between THC and culpability persisted after controlling for blood alcohol concentration, age, and time of accident. They estimated that 2·5% of fatal accidents in France can be attributed to cannabis and 29% to alcohol. Driving after having taken cannabis might increase the risk of motor vehicle crashes 2–3 times16 compared with 6–15 times with alcohol. The policy challenge is to specify a concentration of THC in the blood that legally defines impaired driving.24"
• Cardiovascular effects: Evidence exists to support the adverse cardiovascular effects of cannabis use. Cannabis and THC increase heart rate in a dose-dependent way. These drugs marginally affect healthy young adults who quickly develop tolerance,56 and 57 but concern exists about adults with cardiovascular disease.56 and 57 A case-crossover study by Mittleman and colleagues58 of 3882 patients who had had a myocardial infarction showed that cannabis use can increase the risk of myocardial infarction 4·8 times in the hour after use. A prospective study of 1913 of these individuals reported a dose–response relation between cannabis use and mortality over 3·8 years.59 Risk increased 2·5 times for those who used cannabis less than once a week to 4·2 times in those who used cannabis more than once a week. These findings are supported by laboratory studies that indicate that smoking cannabis provokes angina in patients with heart disease.60
• General disease burden: The public health burden of cannabis use is probably modest compared with that of alcohol, tobacco, and other illicit drugs. A recent Australian study96 estimated that cannabis use caused 0·2% of total disease burden in Australia—a country with one of the highest reported rates of cannabis use. Cannabis accounted for 10% of the burden attributable to all illicit drugs (including heroin, cocaine, and amphetamines). It also accounted for around 10% of the proportion of disease burden attributed to alcohol (2·3%), but only 2·5% of that attributable to tobacco (7·8%).

(Notice it also cites lots of studies supporting safety in most situations etc., but I just quoted what was considered controversial here about the possible risk of death associated with cannabis).

I made the full PDF available here. --Cyclopia^talk 15:42, 6 February 2013 (UTC)

This is most helpful! Now, what is the rate of increase of other activities that also raise heart rate, like shoveling snow? I ask because as I read the bit, I still don't have a sense of balance. It sounds very scary - risk of heart attack raised 4-8 times?! That's scary - there must be oodles of people falling over from smoking pot. Where is the data on that? In other words, we have some data that is usable, but we still need context. Again, Nnauman's contributions can really help here. We already knew that cannabis raises heart rate, which is usually no problem. I imagine that for a certain population, anytime the heart rate is raised, the risk of heart attack goes up. By how much? Is cannabis risk worse than or equal to other random (heart-rate-raising) activities for this population? You see where I'm going with this: if it's equal to shoveling snow, that understanding really needs to accompany the entry about cardiovascular effects (if we find RS for it). I can also look for experts in the field who may have commented on this specifically. That would be a good addition. IMO, people who aren't familiar with the medical field can benefit by hearing a real person talk about the science, helping to put it into context. Offering just the raw data can be very misleading, and in the case of cannabis-caused heart attacks, it would be. petrarchan47tc 20:42, 6 February 2013 (UTC)

Interesting, I just heard on the news "a half hour of shoveling snow increases risk of heart attack more than 4 times for anyone 55 and older". So it IS the same. Now to add this all to the article. (As for the driving risks, this is already in the article.) petrarchan47tc 23:42, 8 February 2013 (UTC)

Another study to add? "In May 2001, "The Chronic Cannabis Use in the Compassionate Investigational New Drug Program: An Examination of Benefits and Adverse Effects of Legal Clinical Cannabis" (Russo, Mathre, Byrne et al.) was completed. This three-day examination of major body functions of four of the five living US federal cannabis patients found "mild pulmonary changes" in two patients.

"This project provides the first opportunity to scrutinize the long-term effects of cannabis on patients who have used a known dosage of a standardized, heat-sterilized quality-controlled supply of low-grade marijuana for 11 to 27 years. Results demonstrate clinical effectiveness in these patients in treating glaucoma, chronic musculoskeletal pain, spasm and nausea, and spasticity of multiple sclerosis. All 4 patients are stable with respect to their chronic conditions, and are taking many fewer standard pharmaceuticals than previously. Mild changes in pulmonary function were observed in 2 patients, while no functionally significant attributable sequelae were noted in any other physiological system examined in the study, which included: MRI scans of the brain, pulmonary function tests, chest X-ray, neuropsy-chological tests, hormone and immunological assays, electroencepha-lography, P300 testing, history, and neurological clinical examination." petrarchan47tc 23:54, 8 February 2013 (UTC)

4 patients is a small sample size, it has no statistic significance. --KDesk (talk) 00:31, 9 February 2013 (UTC)

I wonder if this is a unique case though, "This project provides the first opportunity to scrutinize the long-term effects of cannabis on patients who have used a known dosage of a standardized, heat-sterilized quality-controlled supply of low-grade marijuana for 11 to 27 years". Even a small population can lend interesting data when we have so little to begin with. petrarchan47tc 00:38, 9 February 2013 (UTC)

TIME magazine covered this issue recently, and said "the hour after smoking marijuana is associated with a two-fold to five-fold increase in the risk of heart attack, roughly the same risk seen within an hour of sexual activity." That's what we've been coming up with here. (The article also mentioned the link between stroke and cannabis use was looked at again, but it was confounded by cigarette use.) Does anyone object to my adding this to the article? Yes, a study of cannabis diluted with a cocktail of substances (tobacco/paper) in an uncontrolled environment. — Preceding unsigned comment added by 176.25.36.170 (talk) 17:09, 10 February 2013 (UTC)

Also, are there any more problems with this section, or can we remove the tag now? petrarchan47tc 06:47, 10 February 2013 (UTC)

The issues are:

• I am content to have close to the minimal coverage of health issues in this overview article. Potential risks need to be included, however.
• More discussion can be (and needs to be) in Medical cannabis, Effects of cannabis, and Long-term effects of cannabis. There are sources to update and POV issues in these.
• About deaths; If the present claim "no deaths" remains, it needs to be balanced with reported but rare deaths. Perhaps it is best not to get into the death question.
• I am still not comfortable with a newspaper Opinion piece as a reference for a medical source.
• Time magazine is not a medical source.

Rlsheehan (talk) 18:17, 10 February 2013 (UTC)

TIME can be used in conjunction with other studies (to which we've been referring above). Please specify "opinion piece" and please don't be talking about Grinspoon again. If you have a problem with his inherent RS and how that works, take it to the noticeboard and let us know the result. Please stick to discussing one article on this talk page, we have enough on our plate.

I am asking you specifically what issues you have with the safety section in this article. The reason is that the last two times it seemed like a consensus had been reached, after a few quiet days you went about removing positive things from the safety section (which throws off the whole balance/truth thing). petrarchan47tc 06:45, 11 February 2013 (UTC)

"About deaths; If the present claim "no deaths" remains, it needs to be balanced with reported but rare deaths." Not this again. I still wonder if this issue needs a more formal noticeboard for help. I believe it does. We are grappling with an issue very controversial and important, on a page that gets roughly 10K views a day. And 4 editors are trying to figure out of cannabis did kill people while everyone is saying it hasn't? This is getting ridiculous. I think we need to get a little humility and realize this issues might be bigger than us. petrarchan47tc 06:49, 11 February 2013 (UTC)

A newspaper Opinion is not a reliable source. WP:MEDRS says "Ideal sources for biomedical material include general or systematic reviews in reliable, third-party, published sources, such as reputable medical journals, widely recognised standard textbooks written by experts in a field, or medical guidelines and position statements from nationally or internationally recognised expert bodies." Rlsheehan (talk) 14:47, 11 February 2013 (UTC)

Agreed. If we go cherrypicking quotes, we can find everything and its opposite. They're good RS for other kinds of claims and topics, not medical ones. Let's stick to scientific sources, no matter what newspapers say, on one side or the other. --Cyclopia^talk 15:50, 11 February 2013 (UTC)

Lester Grinspoon researched cannabis, specifically looking for its dangers so he could help his Harvard students to not hurt themselves. He studied the herb for three decades and wrote two books published by Harvard Press. To quote him here regarding his findings is "cherrypicking"? That assumes there are tons of similar cherries out there, I'd love to hear of all the other researchers you are referring to who fit this description. To my knowledge there are VERY few people who have researched cannabis to this degree. petrarchan47tc 20:36, 12 February 2013 (UTC)

Lancet is a good source, and it's the first place I would go to, but one of the reasons is that they have a good correspondence section. This letter raises some of the objections that came to my mind:

http://www.sciencedirect.com/science/article/pii/S0140673610600864

Correspondence: Adverse health effects of non-medical cannabis use

William Tormey, Department of Chemical Pathology, Beaumont Hospital, Dublin 9, Ireland

http://dx.doi.org/10.1016/S0140-6736(10)60086-4

In their Review of the adverse health effects of non-medical cannabis use, Wayne Hall and Louisa Degenhardt (Oct 17, p 1383)1 cite a study by Mittleman and colleagues2 which suggests that smoking marijuana may be a rare trigger of myocardial infarction. However, in that study, only 37 of 124 marijuana-smoking patients reported smoking within 24 h of infarction and more than half the whole study group were cigarette smokers. Mittleman and colleagues do acknowledge limitations to their study.

The Review ignores contrary evidence of the beneficial effects of cannabinoids on the cardiovascular system. These include a protective role in atherosclerosis progression and in cerebral and myocardial ischaemia. Acute exposure to cannabinoids is associated with tachycardia and a small pressor effect, whereas longer-term use is associated with bradycardia and hypotension.3 Such cardiovascular tolerance can occur within 2 days of frequent exposure but disappears quickly when cannabis use is stopped.4

Cannabis smoking, rather than Δ9-tetrahydrocannabinol per se, may be the villain. At this juncture, it is fair to say that the jury remains out on cannabinoids and the heart.5 ...

--Nbauman (talk) 18:32, 13 February 2013 (UTC)

I think Maia Szalavitz in Time is a good WP:RS. Her articles are like a Wikipedia story -- she cites her sources and you can look them up. Her sources are in the medical literature. She does a good job of reporting the medical literature. As the Lancet article also said, one of the difficulties in this kind of research is that marijuana users also frequently smoke cigarettes.

You or I can read The Lancet or Circulation, but when we reference them in the article, we have to do a lot of selection, and that selection doesn't necessarily wind up as NPOV. Sometimes a journalist can write a better, more objective summary of a peer-reviewed article, and the peer-reviewed literature, than we can.

Szalavitz says:

Earlier research, however, found that the hour after smoking marijuana is associated with a two-fold to five-fold increase in the risk of heart attack, roughly the same risk seen within an hour of sexual activity. The authors conclude, “[I]t seems prudent to caution patients with coronary heart disease and those at high risk for cardiovascular disease to abstain from smoking marijuana.”

I think that's a fair summary of the evidence. Marijuana is associated with the same risk as an hour of sexual activity. I don't mind if you quote Mittleman as saying that heart attacks are caused by marijuana, as long as you make it clear that other people believe that it's merely an association. --Nbauman (talk) 18:48, 13 February 2013 (UTC)

I am a member of Wikipedia:WikiProject Bibliographies and received an email that my program I use to find BOOK sources may be useful here (sorry the email is a week old). The list below is small sample of digitizes books on the topic of cannabis and cardiovascular effects - there credibility should not be a problem (scholarly for the most part)- that said they should be view in terms of by whom (author(s)) by publisher and year of publication. Most should be able to view the pages linked below in the titles. Hope this was helpful all the best.Moxy (talk) 19:16, 13 February 2013 (UTC)

• Jeffrey K Aronson (5 January 2012). Side Effects of Drugs Annual: A Worldwide Yearly Survey of New Data in Adverse Drug Reactions. Elsevier. pp. 56–. ISBN 978-0-444-53741-6.
• Wayne Hall; Rosalie Liccardo Pacula (28 November 2003). Cannabis Use and Dependence: Public Health and Public Policy. Cambridge University Press. p. 60. ISBN 978-0-521-80024-2.
• Hamid Ghodse (11 February 2010). Ghodse's Drugs and Addictive Behaviour: A Guide to Treatment. Cambridge University Press. pp. 96–. ISBN 978-1-139-48567-8.
• Donna R. Falvo (30 January 2005). Medical and Psychosocial Aspects of Chronic Illness and Disability, Third Edition. Jones & Bartlett Learning. pp. 217–. ISBN 978-0-7637-3166-3.
• Franjo Grotenhermen; Ethan Russo (2002). Cannabis and Cannabinoids: Pharmacology, Toxicology, and Therapeutic Potential. Psychology Press. pp. 60–. ISBN 978-0-7890-1508-2.
• Glen Hanson; Peter Venturelli; Annette Fleckenstein (29 September 2008). Drugs and Society. Jones & Bartlett Publishers. pp. 364–. ISBN 978-0-7637-5642-0.
• Tatiana Shohov (2003). Medical Use of Marijuana: Policy, Regulatory, and Legal Issues. Nova Publishers. pp. 3–. ISBN 978-1-59033-754-7.
• Thomas Nordegren (1 March 2002). The A-Z Encyclopedia of Alcohol and Drug Abuse. Universal-Publishers. pp. 155–. ISBN 978-1-58112-404-0.
• Michelle Riba; Lawson Wulsin; Melvyn Rubenfire (24 January 2012). Psychiatry and Heart Disease: The Mind, Brain, and Heart. John Wiley & Sons. pp. 234–. ISBN 978-0-470-97512-1. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Joyce H. Lowinson (2005). Substance Abuse: A Comprehensive Textbook. Lippincott Williams & Wilkins. pp. 270–. ISBN 978-0-7817-3474-5.

Thank you for the sources. It seems that the medical community is relatively united on the existence of a small increased risk of MI and stroke, particularly when users have existing cardiovascular problems. I am willing to go along with the consensus here regarding the exact wording and which references to use. Rlsheehan (talk) 21:31, 13 February 2013 (UTC)

So it looks like we just need a proposal for exactly how to present the science, and what articles we're referencing. It has to be said: since the increase in heart rate raises risk of heart attack equal to risk from shoveling snow, or having sex, for those over 55, do scientists also warn people to refrain from the latter activities? What makes cannabis an exclusion, what makes it more dangerous, dangerous enough to deserve a warning like that? Just pointing out that even the most sane arguments can be heavily tinged with what appear to be 'reefer madness' rather than scientific points. Though let me be clear, I do support the TIME piece's affirmation of Nbeuman's take on the study he found, that cannabis raises heart rate = to shoveling snow (4 times).

As for the 2 remaining issues, the Grinspoon comments (which don't need to be in the form of a quotation) and the DEA Judge's:

One interesting fact, the Daily Beast used the DEA's findings as their "Exhibit A" for "Cannabis kills no one" (also there was no consensus for the removal of this bit).

As for Grinspoon, his comments were called cherry-picking, but I still argue, that would require there being other cherries. I am waiting to hear about others who studied cananbis for decades, for an institution like Harvard, and wrote two books on the subject, as Grinspoon has... petrarchan47tc 01:45, 14 February 2013 (UTC)

Not sure whats being asked as the gigantic wall of text above is not a thing i want to spend 4 hours reading - I hope Cannabis kills no one" is not a source. If the question is Cannabis overdose --Moxy (talk) 04:47, 14 February 2013 (UTC)

Sorry, Moxy, I was addressing the editors who've been reading along, it didn't seem like you were joining the talk but rather dropping off links (and thank you, btw). No, I didn't mean to use the Daily Beast as a source. petrarchan47tc 05:07, 14 February 2013 (UTC)

• Lawrence S. Neinstein (2008). Adolescent Health Care: A Practical Guide. Lippincott Williams & Wilkins. p. 911. ISBN 978-0-7817-9256-1.
• David Myland Kaufman (2007). Clinical Neurology for Psychiatrists. Elsevier Health Sciences. p. 524. ISBN 978-1-4160-3074-4.
• Simon Bricker (17 June 2004). The Anaesthesia Science Viva Book. Cambridge University Press. p. 202. ISBN 978-0-521-68248-0.
• Dale Gieringer; Ed Rosenthal; Gregory T. Carter, M.D. (28 October 2008). Marijuana Medical Handbook: Practical Guide to Therapeutic Uses of Marijuana. Ed Rosenthal. p. 24. ISBN 978-0-932551-86-3.

Well after a little time off, its time to apply the research that has been revealed and improve the section to have a neutral point of view. One of the offending sections was an newspaper editorial (not a medical journal) from a retired Harvard prof. I have kept the citation but cleaned up the quote and put it in a more appropriate location. i think this is a reasonable compromise on this item. Lets look at the rest of the section and finish the clean up. Rlsheehan (talk) 19:26, 17 March 2013 (UTC)

This change "(Cannabis has not been proven to have caused deaths) but an association is currently being researched" is being supported by a study which states in the abstract, "Cardiovascular complications in association with marijuana use have been reported during the past three decades. In view of the elevated public interest in this drug's role in pharmacotherapy in the recent years and the aging population of long-term marijuana users from the late 1960s, encounters with marijuana-related cardiovascular adversities may be silently on the rise. The purpose of this article is to increase awareness of the potential of marijuana to lead to cardiovascular disease." Where does it say anything about death, and how is this addition meant to " improve the section to have a neutral point of view"? 174.71.84.85 (talk) 05:37, 20 March 2013 (UTC)

Please read the entire article; Publisher's copywrite does not allow entire text to be linked. Also read [[2]]. Rlsheehan (talk) 12:02, 20 March 2013 (UTC)

Incorrect statements regarding essential oil of cannabis

There is an incorrect statement in one of the paragraphs dealing with essential oil of cannabis. This product has nothing to do with "hash oil" and does not contain significant amounts of psychoactive cannabinoids. This mixture of mono- and sesquiterpenes is responsible for the characteristic odor and aroma of cannabis and is obtained from both fiber and drug strains. This is the fraction of the drug, which is detected by drug sniffing canines. It is steam-distilled from the female flowering tops, there is an entry already under cannabis flower essential oil. It can be used safely in foods and cosmetics and is a component of tea beverages in some parts of Europe. "Hash oil" is something altogether different (an alcoholic extract of hash). It has been illegally traded in the past, but has no longer any relevance, and it is not an extract containing significant amount of the essential oil. Hash oil is NOT a synonym for "essential oil of cannabis". I can add the correct link if there is no objection. Thanks. (67.160.160.76 (talk) 05:58, 15 February 2013 (UTC))

Someone seems to be biased on this...

Much? More like pro-drug bias, since wikipedia is young. Hmmm... — Preceding unsigned comment added by 184.98.124.148 (talk) 09:26, 17 February 2013 (UTC)

Wikipedia is pro drugs in general. The kids and potheads on here talk about the subjective effects and that just makes me laugh. "Feeling of euphoria" when discussing cocaine, etc.

Edit Request - bad grammar - please change

"Contemporary uses of cannabis are as a recreational drug, as religious or spiritual rites, or as medicine;" Should read "Contemporary uses of cannabis are as a recreational or medicinal drug, and as part of religious or spiritual rites." 46.115.118.12 (talk) 05:17, 22 February 2013 (UTC)

 Done I'm sure there're some who'll argue but I like it. ~ Amory (u • t • c) 05:29, 22 February 2013 (UTC)

Edit request - Addictiveness

Just below the section break for Marijuana#Addictiveness, please add

{{main|Cannabis dependence}}

Resulting in

Addictiveness

Main article: Cannabis dependence

Dr. Jack E. Henningfield of NIDA ranked the relative addictiveness of 6 substances (cannabis, caffeine, cocaine, alcohol, heroin and nicotine). Cannabis ranked least addictive, with caffeine the second least addictive and nicotine the most addictive.

This is for consistency with other sections for which a separate, more detailed article is available. Thanks in advance. 67.100.127.70 (talk) 00:15, 3 April 2013 (UTC)

 Done. Thanks for your contributions! ^King Jakob _C2 00:23, 3 April 2013 (UTC)