Cannabis sativa vs. Cannabis indica: Science or Folklore?

Golden Goat or  Sour Diesel?

The bland assurances from medical marijuana dispensaries about the physical and psychological effects of the bewildering array of hybrid plant strains on offer is mostly bunk, claim a growing number of cannabis scientists.

Ethan Russo, a neurologist and pharmacology researcher, as well as the medical director of a biotechnology company, author of numerous books about herbal medicine, and a former faculty member at the University of Washington and the University of Montana, has something to say to marijuana connoisseurs: “There are biochemically distinct strains of Cannabis, but the sativa/indica distinction as commonly applied in the lay literature is total nonsense and an exercise in futility.”

How’s that again? The much-vaunted divide between the cerebral sativa strains, and the sedating, body-oriented effects of indica, are an integral part of marijuana lore and legend. Cannabis growers and biologists endlessly debate the hybridization of new strains. Extolling the virtues of a sativa plant crossed with a plant redolent of indica is a common sales pitch.

In an interview with Dr. Daniele Piomelli for the January 2016 issue of the journal Cannabis and Cannabinoid Research, Russo detailed his disagreement with the assumption that hard evidence exists for this distinction. Dr. Piomelli notes that “sativa is often described as being uplifting and energetic, whereas indica as being relaxing and calming.” Folklore, says Russo. Of course different strains have different effects. But in recent years, says Russo, almost all marijuana has been coming from high-THC strains, with a slight increase in CBD-predominant strains:

"The differences in observed effects in Cannabis are due to their terpenoid content, which is rarely assayed, let alone reported to potential consumers. The sedation of the so-called indica strains is falsely attributed to CBD content when, in fact, CBD is stimulating in low and moderate doses. Rather, sedation in most common Cannabis strains is attributable to their myrcene content, a monoterpene with a strongly sedative couch-lock effect that resembles a narcotic."

And, as for sativa strains: “A high limonene content (common to citrus peels) will be uplifting on mood, while the presence of the relatively rare terpene in Cannabis, alpha-pinene, can effectively reduce or eliminate the short-term memory impairment classically induced by THC.”

Well. I for one do not wish to be caught in the firing line between Dr. Russo and the legions of growers who will beg to differ with his conclusions. For years, it has been accepted wisdom that cannabis comes in two different forms, essentially considered two different species even though they readily interbreed. Even Jean-Baptiste Lamarck, the legendary naturalist of the 18th Century, agreed with the indica and sativa concepts.

But Russo will have none of it: “To paraphrase and expropriate an old Yiddish expression: 12 botanical taxonomists, 25 different opinions…. One cannot in any way currently guess the biochemical content of a given Cannabis plant based on its height, branching, or leaf morphology. The degree of interbreeding/hybridization is such that only a biochemical assay tells a potential consumer or scientist what is really in the plant.”

And finally: “I would strongly encourage the scientific community, the press, and the public to abandon the sativa/indica nomenclature and rather insist that accurate biochemical assays on cannabinoid and terpenoid profiles be available for cannabis in both the medical and recreational markets. Scientific accuracy and the public health demand no less than this.”

Russo’s interview is strong evidence of a viewpoint brought to public attention a few years ago by several others, including the controversial cannabis chemist Jeffrey Raber.

Raber told the L.A. Weekly in 2013 that there was no compelling scientific evidence for the claims routinely made by cannabis dispensaries about the effects of a given colorfully named strain of marijuana. “We took a popular [strain] name, Jack Herer, and found that most didn’t even look like each other. OG whatever, Kush whatever, and the marketing that goes along with it—it’s not really medically designed.”

And the difference between sativa and indica? The cerebral, bracing “mental” high vs. the sleepy, couch-lock “body” high? Forget it, said Raber. The two sub-species are distinguished by morphology only—different structures and appearance, but no hard and fast rules about the quality of the smoking experience. They look different, but that’s no guide to the distribution of THC, CBD, and numerous terpenes that determine the actual quality of the marijuana experience. Moreover, extensive crossbreeding by growers and dealers has helped to obliterate any consistent, meaningful distinctions between sativa and indica highs. (The so-called “skunk” varieties are simply high quality female plants that are prevented from going to seed, which dramatically pushes up the THC content. Almost all of the high-quality weed sold in the U.S., Canada, and the U.K. is skunkweed, so the definition is virtually useless.)

Sativa plants are characteristically tall and rangy, with long branches and long, thin leaves. They evolved, scientists believe, in humid jungle climates. Indica plants are shorter, more compact, and stubbier-looking, with shorter branches and fatter leaves designed for a hot, desert-like climate. It has been assumed that sativas originally came from India, and indicas from Afghanistan. However, indica is the term meant to indicate a plant from India, so right away we find that the situation is all muddled up: the plant from Afghanistan is known by the name of the plant from India. Blame this one on esteemed plant drug investigator Richard Evans Schultes, who apparently mislabeled the plants grown in Afghanistan as C. indica when he drew up the first cannabis taxonomy in the 1970s.

It gets worse. In 2014, at a meeting of the International Cannabis Research Society, research John McPartland with GW Pharmaceuticals announced  the results of his study of genetic markers on the three subspecies of cannabis: C. sativa, C. indica, and a third wild variety, known as C. ruderalis, with very little THC. Any of the three subspecies can be bred as hemp or marijuana, said McPartland. Cannabis sativa should really be known as Cannabis indica, being the Indian variety, while the formerly misnamed indica subspecies should now be called Cannabis afghanica. The name of C. sativa, the high-end connoisseur favorite, would now go to the lowly C. ruderalis, otherwise known as ditch weed, under his new classification scheme.

Quite a lot of changes to a decades-old nomenclature, but it means we are finally getting some serious genetic information about one of the most popular drugs in the world. As Jeremy Daw of The Leaf Online writes: “Starbucks, for example, sources coffee beans from farmers spread across four continents…. In an astonishing feat of global supply chain logistics, Starbucks can now claim to have the ability to trace 94% of its coffee beans all the way back to the exact farm where they were produced.” The cannabis industry, he concludes, still has “a lot of growing up to do.”

Krymon deCesare, chief research director at Steep Hill Halent Lab in Oakland, California, a company developing more sophisticated tests for identifying the various compounds found in marijuana, told AlterNet  that “sativa and indica are only really valid for describing the physical characteristics of the cannabis strain in a given environment. They are not nearly as reliable as terms for making assumptions about energy versus couch lock.” To the extent that there is a grain of truth in the basic division between the mind high of sativa and the body high of indica, as traditionally classified, deCesare believes the culprit is myrcene. Based on the analysis of more than 100,000 samples, deCesare says that his team found “consistently elevated levels of the terpenoid myrcene in C. indica as compared to C. sativa. Myrcene is the major ingredient responsible for ‘flipping’ the normal energetic effect of THC….”

Ethan Russo invokes his notion of the “entourage effect,” in which the distinctive highs normally associated with indica and sativa are in fact the result of a complex combination of many different cannabinoids and terpenes working in harmony. Teasing that apart in the lab is not a cheap or easy affair. If you don’t know your terpene levels, says Russo, than you can’t compute your relative chances of full couch-lock. And even if terpene levels are known, the same pot plant, when smoked, can still cause one person to become energized and talkative, while another person may just fall asleep. Same chemicals, different metabolisms. One person’s happy, giggly high is another person’s paranoid bad trip.

The result of this recent research is to bolster the general suspicion about medical marijuana dispensaries: The names of various marijuana varieties are not only stupid and immature, but also completely misleading and unhelpful. Coherent labeling will require much more than listing relative THC percentages. We’ve only just begun.

A Chemical Peek at Modern Marijuana

Researchers ponder whether ditch weed is better for you than sinsemilla.

Australia has one of the highest rates of marijuana use in the world, but until recently, nobody could say for certain what, exactly, Australians were smoking. Researchers at the University of Sydney and the University of New South Wales recently analyzed hundreds of cannabis samples seized by Australian police, and put together comprehensive data on street-level marijuana potency across the country. They sampled police seizures and plants from crop eradication operations. The mean THC content of the samples was 14.88%, while absolute levels varied from less than 1% THC to almost 40%.  Writing in PLoS one, Wendy Swift and colleagues found that roughly ¾ of the samples contained at least 10% total THC. Half the samples contained levels of 15% or higher—“the level recommended by the Garretsen Commission as warranting classification of cannabis as a ‘hard’ drug in the Netherlands.”

In the U.S., recent studies have shown that THC levels in cannabis from 1993 averaged 3.4%, and then soared to THC levels in 2008 of almost 9%. THC loads more than doubled in 15 years, but that is still a far cry from news reports erroneously referring to organic THC increases of 10 times or more.

CBD, or cannabidiol, another constituent of cannabis, has garnered considerable attention in the research community as well as the medical marijuana constituency due to its anti-emetic properties. Like many other cannabinoids, CBD is non-psychoactive, and acts as a muscle relaxant as well. CBD levels in the U.S. have remained consistently low over the past 20 years, at 0.3-0.4%. In the Australian study, about 90% of cannabis samples contained less than 0.1% total CBD, based on chromatographic analysis, although some of the samples had levels as high as 6%.

The Australian samples also showed relatively high amounts of CBG, another common cannabinoid. CBG, known as cannabigerol, has been investigated for its pharmacological properties by biotech labs. It is non-psychoactive but useful for inducing sleep and lowering intra-ocular pressure in cases of glaucoma.

CBC, yet another cannabinoid, also acts as a sedative, and is reported to relieve pain, while also moderating the effects of THC. The Australian investigators believe that, as with CBD, “the trend for maximizing THC production may have led to marginalization of CBC as historically, CBC has sometimes been reported to be the second or third most abundant cannabinoid.”

Is today’s potent, very high-THC marijuana a different drug entirely, compared to the marijuana consumed up until the 21st Century? And does super-grass have an adverse effect on the mental health of users? The most obvious answer is, probably not. Recent attempts to link strong pot to the emergence of psychosis have not been definitive, or even terribly convincing. (However, the evidence for adverse cognitive effects in smokers who start young is more convincing).

It’s not terribly difficult to track how ditch weed evolved into sinsemilla. It is the historical result of several trends: 1) Selective breeding of cannabis strains with high THC/low CBD profiles, 2) near-universal preference for female plants (sinsemilla), 3) the rise of controlled-environment indoor cultivation, and 4) global availability of high-end hybrid seeds for commercial growing operations. And in the Australian sample, much of the marijuana came from areas like Byron Bay, Lismore, and Tweed Heads, where the concentration of specialist cultivators is similar to that of Humboldt County, California.

The investigators admit that “there is little research systematically addressing the public health impacts of use of different strengths and types of cannabis,” such as increases in cannabis addiction and mental health problems. The strongest evidence consistent with lab research is that “CBD may prevent or inhibit the psychotogenic and memory-impairing effects of THC. While the evidence for the ameliorating effects of CBD is not universal, it is thought that consumption of high THC/low CBD cannabis may predispose users towards adverse psychiatric effects….”

The THC rates in Australia are in line with or slightly higher than average values in several other countries. Can an increase in THC potency and corresponding reduction in other key cannabinoids be the reason for a concomitant increase in users seeking treatment for marijuana dependency? Not necessarily, say the investigators. Drug courts, coupled with greater treatment opportunities, might account for the rise. And schizophrenia? “Modelling research does not indicate increases in levels of schizophrenia commensurate with increases in cannabis use.”

One significant problem with surveys of this nature is the matter of determining marijuana’s effective potency—the amount of THC actually ingested by smokers. This may vary considerably, depending upon such factors as “natural variations in the cannabinoid content of plants, the part of the plant consumed, route of administration, and user titration of dose to compensate for differing levels of THC in different smoked material.”

Wendy Swift and her coworkers call for more research on cannabis users’ preferences, “which might shed light on whether cannabis containing a more balanced mix of THC and CBD would have value in the market, as well as potentially conferring reduced risks to mental wellbeing.”

Swift W., Wong A., Li K.M., Arnold J.C. & McGregor I.S. (2013). Analysis of Cannabis Seizures in NSW, Australia: Cannabis Potency and Cannabinoid Profile., PloS one, PMID: 23894589

Graphics Credit: http://420tribune.com

Strong Pot: What Do Schizophrenics Think?

Small study asks patients for their opinions.

The theory, fiercely debated in the research community, that strong cannabis can actually cause schizophrenia—or is associated with relapse in schizophrenics who smoke it—is the subject of a small study from Switzerland on outpatient schizophrenics, some of whom were pot smokers.

 A study of this kind, with only 10 subjects, verges on the anecdotal. Nonetheless, it is worth a look, just to see if any verification of the theory lurks therein.

In their paper for the open access Harm Reduction Journal—“Do patients think cannabis causes schizophrenia? A qualitative study on the causal beliefs of cannabis using patients with schizophrenia”—psychiatric workers with the Research Group on Substance Use Disorders interviewed patients who attended an outpatient clinic at the Psychiatric University Hospital in Zurich. The researchers did it because, as the paper states, “patients’ beliefs on the role of cannabis in the pathogenesis of schizophrenia have—to our knowledge—not been studied so far…”

“None of the patients described a causal link between the use of cannabis and their schizophrenia,” the researchers determined. However, several of the schizophrenics did have their own version of a disease model to account for their illness. Five of the patients attributed their schizophrenia to “upbringing under difficult circumstances,” and three placed the blame on “substances other than cannabis (e.g. hallucinogens).” The remaining two patients gave “other reasons.”

Interestingly, four of the patients “considered cannabis a therapeutic aid and reported that positive effects (reduction of anxiety and tension) prevailed over its possible disadvantages (exacerbation of positive symptoms).” The authors conclude that excluding schizophrenic patients from treatment settings because of marijuana use “may cause additional harm to this already heavily burdened patient group.”

Graphics Credit: http://www.salem-news.com

The Drug Myth That Will Not Die

Brits still pushing marijuana/schizophrenia connection.

If at first you don’t succeed....

The UK Telegraph reports that scientists at the Institute of Psychiatry in King's College London injected (yes, injected) 22 healthy men with high potency THC (not marijuana), and recorded the results. According to the leader of the study team, Dr. Paul Morrison, "These findings confirm that THC can induce a transient acute psychological reaction in psychiatrically well individuals."

The Telegraph article said the researchers found that the "extent of psychotic reaction" was not related to "the degree of anxiety or cognitive impairment" in the men.

Mary Brett, vice president of Europe Against Drugs, said: "This shows that anyone who is healthy can become psychotic by smoking cannabis. They don't already have to have a mental illness. Healthy people can become psychotic."

Well, no. Observant readers will no doubt find all of this familiar: More than a year ago, a national hysteria over “skunk” cannabis was sparked in Great Britain when the University College of London produced a study purporting to show that strong pot was literally driving people crazy. The lunacy peaked with Prime Minister Brown’s description of new strains of cannabis as 'lethal.' At the time, the London Guardian reported that "Whitehall's own panel of experts has concluded that increased marijuana use has not been matched by a corresponding rise in mental illness."

Against the advice of her own drug advisers, then-Home Secretary Jacqui Smith restored cannabis from class C to the “harder” class B status because of mental health concerns. British health authorities maintained that "skunk" cannabis was linked to the onset of schizophrenia. Since no one knows what, exactly, causes schizophrenia, and since recent findings continue to point toward genetic causes, this was a triply astonishing claim.

Colin Blakemore, a prominent professor of neuroscience at the Universities of Oxford and Warwick, tackled the issue of “pot so strong it can make you psychotic” in an article for the Guardian:

“And what of the alarming stories of horrifying powerful "skunk"? Some newspapers have told us that the level of THC, the active ingredient, in street cannabis today is 20 or 30 times higher than 10 years ago. That would be rather surprising, given that THC content was 7 per cent on average in 1995. In reality, two studies, due to be published later this year, concluded that the average THC content has doubled.”

With the latest report, King’s College has once again proven that if you inject someone with massive doses of THC, he or she will find the experience dramatically unpleasant. So do monkeys. Years ago, when researchers injected test monkeys with synthetic THC approximately one hundred times more powerful than the naturally occurring substance, the monkeys fell down and didn’t move. This was dramatic proof of... nothing in particular. But it was sensational and it made headlines.

Meanwhile, the solid fact that a minority of marijuana users experience strong withdrawal symptoms when they abstain—an important and verifiable scientific finding—remains largely unknown to the general public.


Photo Credit: http: www.healthjockey.com

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U.K. Marijuana Panic Continues

British Prime Minister plans to stiffen pot penalties.

The national hysteria over "skunk" marijuana shows no signs of abating in Great Britain, as Prime Minister Gordon Brown is poised to overrule his advisors and reclassify cannabis as a more dangerous drug. Lost in the debate is any semblance of reasonable discussion about scientific research on marijuana.

British health authorities continue to find the basics of cannabis to be an inscrutable mystery. Some months ago, they declared that "skunk" cannabis was linked to the onset of schizophrenia. Since no one knows what, exactly, causes schizophrenia, and recent findings continue to point toward genetic causes, this was a doubly astonishing claim.

Now, continuing in the same vein of misinformation, The University College of London reports that different strains of marijuana cause different types of psychological maladies. Recently, Prime Minister Brown "publically described new strains of cannabis as 'lethal,' as if they could trigger a fatal overdose," according to an editorial in the Guardian. The Guardian went on to note that "Whitehall's own panel of experts has concluded that increased marijuana use has not been matched by a corresponding rise in mental illness."

The move to shift marijuana to Class B status from its current Class C designation has been fueled by these dubious reports. As long as British politicians continue to believe that something called "skunk" is a new and lethal derivative of marijuana, and that it causes psychosis, schizophrenia and suicide, no substantive debate on cannabis regulation can possibly take place. Colin Blakemore, a prominent professor of neuroscience at the Universities of Oxford and Warwick, tackled the issue in an article for the Guardian:

And what of the alarming stories of horrifying powerful "skunk"? Some newspapers have told us that the level of THC, the active ingredient, in street cannabis today is 20 or 30 times higher than 10 years ago. That would be rather surprising, given that THC content was 7 per cent on average in 1995. In reality, two studies, due to be published later this year, concluded that the average THC content has doubled.

Professor David Clark, a British psychologist who maintains a substance abuse information service called Wired In, writes on his blog: " I have to confess that I really cannot see what reclassifying the drug will do, other than criminalise and alienate more of our young people. It won't reduce harms that the drug can cause to some people. In saying this, I am not arguing that cannabis is safe - but nor are alcohol, tobacco and a wide range of prescription drugs which are all legal. "

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