Archive for the 'Cannabis' category

Marijuana Use, Abuse and Dependence Increased Over the Past Decade

Oct 23 2015 Published by under Cannabis, Drug Abuse Science

A new paper from Hasin and colleagues at JAMA Psychiatry reviews data:

from NESARC and from the National Institute on Alcohol Abuse and Alcoholism
2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions–III (NESARC-III), a survey of 36,309 new participants.
The NESARC field procedureswere similar to those in NESARC-III.

There are really three key observations, although the tables also break down the findings by sex, age, race/ethnicity, education level, etc.

First, past year use of marijuana went from 4.1% to 9.5% of the sampled populations. Interesting, but hey, could just be more people feeling free to try it out, right?

Second finding looked at prevalence of meeting DSM-IV criteria for a Marijuana Use Disorder (including Abuse and Dependence subcategories) in the past year. This measure went from 1.5% to 2.9% of the population.

The third finding is that if you condition only upon those individuals who have tried marijuana at least once in the past year, the rate of a Marijuana Use Disorder went from 35.6% to 30.6%.

This is all relevant to a few themes we've discussed before on the blog.

I don't see how you can view these data other than in a context of growing liberalization of medical marijuana laws and availability of marijuana. This refutes the occasional position struck by the pot fans that changes in legal status and attitude won't change use rates because everyone who wants to smoke marijuana already does. Clearly the US population undergoes significant changes in exposure to marijuana. In this case only over a decade.

My position has also been that, in general, as you increase the number of people who are exposed to a given drug you are going to see an increase in problems related to that drug. In the absence of other information, we must start our estimate of that rate from what we observe at a given time. The first two numbers in the study confirm this. As use rates increased, so did rates of meeting criteria for DSM-IV diagnosis of a MUD.

The conditional probability measure also addresses this phenomenon, perhaps in an even better way. I have mentioned before that it is really hard to assess conditional probability of dependence between drugs that feature significant base-rate exposure differences. You can't help but assume there is going to be a curve whereby the more democratic the exposure, the larger will be the occasional user population. That is, I assume some sort of nonlinearity is going to occur against the general estimation I mention above. I presume the lower the incidence of exposure to a given drug, perhaps the higher the conditional probability of dependence and the higher the incidence of exposure, the lower the conditional probability.

In this case, I'd say the change in conditional probability is not that significant. Something around a third of those who smoke marijuana in a given year are meeting criteria for a MUD across a doubling of the incidence of exposure. The curve is still pretty linear although I assume we will be getting another jump in a decade and can see how this curve shapes up.

This estimate of a MUD is really high to my eye, no doubt because it includes abuse and dependence together. Perhaps the data I usually think about (7-9% dependence rate) references dependence without abuse...I have to go check on that. In case you are wondering, the difference really boils down to symptoms of tolerance (diminished effect at same dose, increasing dose to get desired effect) and withdrawal, as well as some indicators of uncontrolled use relative to a person's intentions.

Now interestingly the authors reference another similar study (NSDUH) that didn't find an increase in prevalence that was so large- only 12% reported by Pacek et al, 2015. The present authors suggest more detailed questioning in the NESARC approach may explain the difference.

9 responses so far

The Daily Show is just plain wrong on pot being non-addictive

Apr 21 2015 Published by under Alleged Profession, Cannabis, Drug Abuse Science

In the 420 bit from this week, Jessica Williams asserts that marijuana is "a non-addictive proven medical treatment".

Marijuana is most certainly addictive.

In 2012, 17.5% of all substance abuse treatment admissions had marijuana as their primary abused drug. Alcohol alone was 21.5%, heroin 16.3% and cocaine 6.9%.

Daily marijuana smokers use 3 times a day on average and have little variability from day to day.

Pregnant women are unwilling or unable to stop smoking pot almost daily. Increasing numbers of pregnant women are seeking help to discontinue pot use.

At least one woman found out her hyperemesis during pregnancy was the pot, not morning sickness.

Marijuana is addictive in adolescents.

When adolescents stop smoking weed, their memory gets better.

About six percent of High School seniors are smoking pot almost every day.

Clinical trials of medications to help people who are addicted to marijuana stop using are far from rare.

Francophones are addicted to pot.

Yes, Dutch people are addicted to pot.

Many Cases of cannabis hyperemesis syndrome are unable to stop smoking pot, even though it is severely incapacitating them.

Marijuana is addictive.

About 37% of frequent pot users will transition to dependence in three years.

Oh, and pot users are not awesome, friendly and mellow, actually nondependent users are impulsive and hostile on the day they use pot compared with nonsmoking days.

57 responses so far


Mar 25 2015 Published by under Cannabis, Public Health

I just had this genius idea.

A public science service modeled on 23andme where you send in your pot sample for both genetic analysis ("You have new strain-relatives, want to connect and share experiences?") and content of various cannabinoids and what not. Add in some health survey stuff and away we go.

3 responses so far

Health report from Colorado: Recreational marijuana harms

Dec 15 2014 Published by under Cannabis, Drug Abuse Science

a Reader put me onto a new Viewpoint in JAMA:

Monte AA, Zane RD, Heard KJ. The Implications of Marijuana Legalization in Colorado.JAMA. 2014 Dec 8. doi: 10.1001/jama.2014.17057. [Epub ahead of print][JAMA; PubMed]

The authors are from the Department of Emergency Medicine, University of Colorado and the Rocky Mountain Poison and Drug Center. They set out to describe a few health stats from before and after the recreational legalization of marijuana.

Interesting tidbits:

However, there has been an increase in visits for pure marijuana intoxication. These were previously a rare occurrence, but even this increase is difficult to quantify. Patients may present to emergency departments (EDs) with anxiety, panic attacks, public intoxication, vomiting, or other nonspecific symptoms precipitated by marijuana use. The University of Colorado ED sees approximately 2000 patients per week; each week, an estimated 1 to 2 patients present solely for marijuana intoxication and another 10 to 15 for marijuana-associated illnesses.

This one is obviously frustratingly anecdotal in that there is no real measure of the rate before legalization.

The one on cyclic vomiting syndrome is better:

The frequent use of high THC concentration products can lead to a cyclic vomiting syndrome. Patients present with severe abdominal pain, vomiting, and diaphoresis; they often report relief with hot showers. A small study at 2 Denver-area hospitals revealed an increase in cyclic vomiting presentations from 41 per 113 262 ED visits to 87 per 125 095 ED visits (prevalence ratio, 1.92) after medical marijuana liberalization (A. A. Monte, MD, unpublished data, December 2014).

We've discussed the phenomenon of cannabis hyperemesis before on the blog. One thing we do have to be careful about is that since it has only been recently that the medical community has been alerted to the possibility of cannabis hyperemesis, we should expect the detection rate to increase. Thus, even against a stable rate of cannabis hyperemesis I would expect the reported rate to be increasing.

The University of Colorado burn center has experienced a substantial increase in the number of marijuana-related burns. In the past 2 years, the burn center has had 31 admissions for marijuana-related burns; some cases involve more than 70% of body surface area and 21 required skin grafting. The majority of these were flash burns that occurred during THC extraction from marijuana plants using butane as a solvent.

This is the e-cigarette and vape market at work people. In South Florida they apparently call it 'Budda'.

Apparently some basic pharmacology 101 would be of help to the good citizens of Colorado.

Edible products are responsible for the majority of health care visits due to marijuana intoxication for all ages. This is likely due to failure of adult users to appreciate the delayed effects of ingestion compared with inhalation. Prolonged absorption complicates dosing, manufacturing inconsistencies lead to dose variability

Interesting. I recall the language in the original initiative was very vague about product testing, labeling, etc. Looks like this is a problem.

Ten to 30 mg of THC is recommended for intoxication depending on the experience of the user; each package, whether it is a single cookie or a package of gummy bears, theoretically contains 100 mg of THC. Because many find it difficult to eat a tenth of a cookie, unintentional overdosing is common. Furthermore, manufacturing practices for marijuana edible products are not standardized. This results in edible products with inconsistent THC concentrations, further complicating dosing for users. According to a report in the Denver Post, products described as containing 100 mg of THC actually contained from 0 to 146 mg of THC.8

Oh, and the children. Don't forget about the children.

The most concerning health effects have been among children. The number of children evaluated in the ED for unintentional marijuana ingestion at the Children’s Hospital of Colorado increased from 0 in the 5 years preceding liberalization to 14 in the 2 years after medical liberalization.3 This number has increased further since legalization; as of September 2014, 14 children had been admitted to the hospital this year, and 7 of these were admitted to the intensive care unit. The vast majority of intensive care admissions were related to ingestion of edible THC products.

This Viewpoint certainly draws attention to the edibles/consumables products as being a problem. Seems pretty clear that maturation of product regulation would be a start, so that people are informed about what they are getting. This should probably be supplemented with some sort of public information campaign on the pharmacokinetics of ingested products compared with smoking marijuana. And, you know, keep it away from your kids.

13 responses so far


Nov 05 2014 Published by under Cannabis, Public Health

Looks like both Oregon and Alaska passed initiatives to legalize the recreational use of marijuana.


Oregon's initiative.

Alaska's initiative.


(1) A person commits the offense of use of marijuana while driving if the person uses any marijuana while driving a motor vehicle upon a highway.

(2) The offense described in this section, use of marijuana while driving, is a Class B traffic violation.

a related item that I like because it calls for research:

(4) On or before January 1, 2017, the commission shall:

(a)Examine available research, and may conduct or commission new research, to investigate the influence of marijuana on the ability of a person to drive a vehicle and on the concentration of delta-9 tetrahydrocannabinol in a person's blood, in each case taking into account all relevant factors; and
(b) Present the results of the research to the Legislative Assembly and make recommendations to the Legislative Assembly regarding whether any amendments to the Oregon Vehicle Code are appropriate.

weird exception:

(13) "Marijuana extract" means a product obtained by separating resins from marijuana by solvent extraction, using solvents other than vegetable glycerin, such as butane, hexane, isopropyl alcohol, ethanol, and carbon dioxide.

aha, found this part:

SECTION 57. Homemade marijuana extracts prohibited. No person may produce, process, keep, or store homemade marijuana extracts.

so you can't make solvent extractions for home use but you *can* make vegetable glycerine extractions. Weirder. If the idea is to keep people from doing dangerous stuff with explosive solvents, this would be solved short of prohibiting "keep, or store homemade marijuana extracts", no?

In case you are wondering, vegetable glycerine extracts can be used in vape pen / e-cig type devices.


(b) Nothing in this chapter is intended to allow driving under the influence of marijuana or to supersede laws related to driving under the influence of marijuana.

14 responses so far

Szalavitz on marijuana addiction

Oct 15 2014 Published by under Cannabis, Cocaine, Drug Abuse Science

If I'm going to bash a journalist when she writes something horrible about drug abuse, I must take pains to congratulate her when she writes something pretty good.

Maia Szalavitz' latest "Of course Marijuana addiction exists and it's (almost) all in your head" is actually not bad.
Continue Reading »

4 responses so far

Repost: The War on Drugs Didn't Work, Eh?

Sep 02 2014 Published by under Cannabis, Drug Abuse Science, Public Health

There's a strawman-tilting screed up over at from my current favorite anti-drug-war-warrior Maia Szalavitz. She's trying to assert that Trying to Scare Teens Away From Drugs Doesn’t Work.

In this she cites a few outcome studies of interventions that last over relatively short periods of time and address relatively small populations. I think the most truthful thing in her article is probably contained in this quote:

Another study, which used more reliable state data from the CDC’s Youth Risk Behavior Survey, concluded that “When accounting for a preexisting downward trend in meth use, effects [of the Montana Meth Project] on meth use are statistically indistinguishable from zero.”

This points out the difficulty in determining broad, population based outcomes from either personal introspection (where a lot of the suspicion about anti-drug messaging comes from, let's face it) or rather limited interventions. Our public policy goals are broad- we want to affect entire national populations...or at least state populations. In my view, we need to examine when broad national popular behavior shifted, if it did, if we want to understand how to affect it in the future.

The following originally appeared 21 July 2008.

If you are a reader of my posts on drug abuse science you will have noticed that it rarely takes long for a commenter or three to opine some version of "The (US) War on Drugs is a complete and utter failure". Similarly, while Big Eddie mostly comments on the liberty aspects (rather than the effectiveness) of the WoD himself, a commenter to his posts will usually weigh in, commenting to a similar effect.

Now I'm open to all the arguments about personal liberty trade offs, economic costs, sentencing disparities, violations of other sovereign nations and the like. Nevertheless, I'm most interested in the fundamental question of whether the War on Drugs worked. That is, to reduce drug use in the US. For those who believe it has not worked, I have a few figures I would like explained to me.

Continue Reading »

10 responses so far

Medical marijuana "researcher" fired by U of A

Jul 02 2014 Published by under Cannabis, Public Health, Science Politics

From the LA Times:

The University of Arizona has abruptly fired a prominent marijuana researcher who only months ago received rare approval from federal drug officials to study the effects of pot on patients suffering from post traumatic stress disorder.

The firing of Suzanne A. Sisley, a clinical assistant professor of psychiatry, puts her research in jeopardy and has sparked indignation from medical marijuana advocates.

I bet. Interestingly I see no evidence on PubMed that this Sisley person has any expertise in conducting research at all. I'm not saying I need exhaustive credentials but I'd like to see a published study or two.

Cue the usual raving about how this is all a vast right wing conspiracy to keep down miraculous medication...

Sisley charges she was fired after her research – and her personal political crusading – created unwanted attention for the university from legislative Republicans who control its purse strings.

“This is a clear political retaliation for the advocacy and education I have been providing the public and lawmakers,” Sisley said. “I pulled all my evaluations and this is not about my job performance.”

Well, this IS Arizona we're talking about. I'm going to want to see more* but I guess I am going to have to score myself as sympathetic to the notion that this was a political squelching.
Still, the University is denying the charge...

University officials declined to explain why Sisley’s contract was not renewed, but objected to her characterization.

“The university has received no political pressure to terminate any employee,” said Chris Sigurdson, a university spokesman. He said the university embraces research of medical marijuana, noting that it supported a legislative measure in 2013 permitting such studies to be done on state campuses.

Ok, "embraces", eh? We'll see if that turns out to be true.

h/t: clbs

*if this holds true to form the University will be compelled to make a case for how she wasn't competent at the "clinical assistant professor" category of association with U of A.

4 responses so far

CPDD 2014: The XLR-11 synthetic cannabinoid is looking nastier by the day

XLR-11_structureA session on synthetic cannabinoids at the Experimental Biology meeting in April included a talk on nephrotoxicity consequent to use of synthetic cannabinoid products. I covered it in a post. As with a prior report of Cases in Wyoming, the scientist from Oregon reported being able to identify XLR-11 in two of the cases presented. There is not much available on PubMed at the moment regarding the effects of this cannabimimetic. (The XLR-11 structure at the right is courtesy of "meodipt" who submitted it to the Wikipedia page for free use.)

New data presented by Michael Gatch at the recent meeting of the College on Problems of Drug Dependence in San Juan, PR (lovely venue, btw) caught my eye because of an unusual property of XLR-11. Previously, Gatch has looked at a lengthy series of synthetic cathione ("bath salt") drugs in mouse locomotor and rat drug-discrimination assays. This new work is similar, save for the different drug class, so if you want some background reading, that prior paper would be a good complement.

The key, for me, was the drug-discrimination data. This is an assay in which animals are trained to discriminate saline from a reference drug, in this case good old Δ9Tetrahydrocannabinol (THC). In essence the rat is reinforced for responding on one lever if it has received saline just prior to the operant session and on the other lever if it has received THC. Then, on critical test days, you can substitute a dose of some other drug and determine the extent to which the rat responds on the drug-paired versus saline-paired lever. As I've mentioned before, this seems imprecise to the newcomer since seemingly any intoxicant would be scored as "drug" to a rat. Not so. They are actually highly specific in categorizing drugs of similar pharmacological activity.

The interesting thing in the presentation by Gatch was that he showed time-course with bins of about 5 minutes after the start of the session. One drug, XLR-11, popped out as having rapid onset of activity (i.e., full THC responding at 5 min when it takes maybe 10 or 15 for this to occur for THC itself) and a short duration of action (THC-lever responding disappeared after about 15 minutes). I say it popped out because out of a series of cannabimimetic drugs he presented, this one was the only one to have this profile (to my recollection).

This is interesting because in a general sense this tells me two things. First, this is the profile of a drug that is going to engender rapid on/off subjective effects and therefore very likely frequent re-dosing. From a comparative perspective this sounds like enhanced abuse liability to me...i.e., better chances of causing addiction.

The second aspect only hit me when I recalled that XLR-11 was the compound associated with nephrotoxicity. Now, admittedly, it may be the case that XLR-11 itself has a pyrolosis product produced during the smoking of plant matter containing it. But it also strikes me that this rapid on/off pharmacological profile might lead to recreational users simply using more of the products containing this compound than they ever would of products containing some longer acting synthetic cannabinoid. And that might get us back to thinking about what is contained in the various plants used in the products being sold to users.

9 responses so far

Hyperemesis associated with synthetic cannabinoid products

Mar 07 2014 Published by under Cannabis, Drug Abuse Science

As you know, Dear Reader, a cyclical vomiting syndrome is often associated with chronic cannabis smoking. I've written about it a few more times (here, here, here) and you can check out additional posts at Addiction Inbox (here, here). I urge you to read through the comments posted under all of these blog entries. The numbers definitely rival the published Case Reports in number of affected individuals. Clearly there continues to be many folks suffering who go initially undiagnosed.

A Reader sent me a link to a medical diagnosis challenge published in the Well section of the New York Times recently which returned my interest to the topic. Mostly due to the following comment in the solution column:

Sure enough, there it was – two recent case reports describing several regular synthetic marijuana users who developed a syndrome that was indistinguishable from cannabinoid hyperemesis caused by the real stuff.

I had not seen any such reports so I went looking and found one of them on PubMed.

Hopkins CY, Gilchrist BL. A case of cannabinoid hyperemesis syndrome caused by synthetic cannabinoids. J Emerg Med. 2013 Oct;45(4):544-6. doi: 10.1016/j.jemermed.2012.11.034. Epub 2013 Jul 26.

By now, the diagnosis sounds very familiar. A 30 year old man presented at the ED with nausea and vomiting. He reported a prior history of such episodes, including gastro-enterology workups, scans, endoscopies, etc. Nothing that would explain his symptoms was ever found. The patient had found that hot showers relieved his pain and took several showers per day.

Naturally the patient had started using cannabis at the age of 13 and had been smoking several times per day for years.

Up until this point, everything is very familiar.

This particular individual had been cannabis free for 6 months due to legal surveillance under parole. After cleverly determining with over-the-counter tests that synthetic marijuana products (brand names of K2 and Spice were popular early in the cycle and have come to be familiar as semi-generic terms) didn't trigger cannabinoid positives:

...he quickly resumed his daily smoking habits and in the month before presentation was often smoking synthetic marijuana hourly, including waking up several times at night to get high.

The patient claimed that in the 2 months prior to presentation he'd been using "Scooby Snacks (sic)*" brand exclusively and provided some to the research team. This is cool because the team identified the cannabinoids in the product. It contained several, "JWH-018, JWH-073, JWH-122, AM-
2201, and AM-694" and they also found the patient's urine to be positive for JWH-018, JWH-073 and AM-2201.

As a bit of a sidebar, I really don't know why particular combinations are included in various synthetic cannabis products. It is unclear if it is accident of supply, illicit manufacturers who just throw stuff together at random, the end of the batches or something more intentional. There is an interesting paper from the Fantegrossi group (Brents et al, 2013) that suggests the possibility of synergistic effects.

Returning to the case report, on three month followup it was found the patient manged to remain abstinent and reported remission of his symptoms after the first 2 weeks.

Okay, so typical story for cannabinoid hyperemesis syndrome and in this case the patient had been exposed to multiple cannabinoid full agonists instead of delta-9-tetrahydrocannabinol prior to current episode. Of course his history suggests strongly that it was cannabis smoking that created his liability for the episodes in the first place.

One take-away message over the past several years is that we've rapidly gone from a point where nobody knows cannabis can cause a vomiting syndrome to some reasonable awareness. This is fantastic. The greater awareness, the greater the chances of rapid and accurate diagnosis. If you read the case reports you will see extensive and expensive gastrointestinal testing and diagnostic work in the history of many individual patients. Realization on the part of the patients that they should mention their cannabis smoking helps. Realization on the part of medical staff that they should ask about cannabis helps.

Knowledge can be a powerful bit of assistance for health care.

*more likely Scooby Snax?

One response so far

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