THC and altitude

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THC and altitude

by drpw » Tue Jan 11, 2011 5:33 pm

There are people here who are much more intelligent than me and I am hoping this might pique their interests. It was stated on the Ritalin thread that Ritalin is a vasoconstrictor and might lead to more complications at altitude. This got me thinking about another drug that is commonly used in the mountains and the effect it might have on performance since it seems that the pot smokers of our group of climbers cope with altitude slightly better than those who don't puff. Anyone wanna discuss/explain while I go take a, uh, smoke break?

Cerebrovascular Effects:

Matthew & Wilson[xxxiv] found "In experienced marijuana smokers, marijuana smoking was accompanied by a significant bilateral increase in cerebral blood flow (CBF) especially in the frontal regions and cerebral blood velocity." Tunving et al[xxxv], studying long-term cannabis users found decreases in cerebral blood flow during the early stages of detoxification, reverting to normal after 9-60 day follow-up. Similar results were found by Lundqvist et al[xxxvi] - "Cerebral blood flow (CBF) was measured in 12 long-term cannabis users shortly after cessation of cannabis use (mean 1.6 days). The findings showed significantly lower mean hemispheric blood flow values and significantly lower frontal values in the cannabis subjects compared to normal controls" Ellis et al[xxxvii] found "Anandamide (AN) and delta 9-THC similarly induced a dose-dependent dilation (of cerebral arterioles) starting at concentrations as low as 10(-12) M. Maximum dilation for AN was 25% and that for delta 9-THC 22%. Topical coapplication of indomethacin, a cyclooxygenase inhibitor, completely blocked dilation"

Bloom et al[xxxviii] found different areas of the brain to have different blood-flow responses to THC · "Changes in regional cerebral blood flow were observed in 16 of the 37 areas measured." Stein et al[xxxix] in the rat, an O"Leary et al[xl] in human recreational users, also found wide variations in cerebrovascular response in different brain regions.

Strokes and Neuroprotectivity:

There are a number of case studies describing patients who have suffered strokes following or during cannabis use, some, but not all,of these cases can be explained by use of other drugs (alcohol or stimulants). Cooles & Michaud[xli] report a case history of a patient suffering a stroke following a heavy bout of cannabis smoking. Alvaro et al[xlii] reported another case history "of a young man and heavy cannabis smoker who suffered posterior cerebral artery infarction during his first episode of coital headache"In a further case history, Lawson & Rees[xliii] reported "A 22-year-old man with a five-year history of drug and alcohol abuse presented with a left hemiparesis preceded by three transient ischaemic attacks, two of which occurred whilst smoking cannabis" although in response, McCarrom & Thomas[xliv] stressed the likely role of alcohol or other drugs in the etiology of such strokes. Mouzak et al[xlv] described "Three male patients (mean age 24.6 years) who were heavy cannabis smokers presented with transient ischemic attacks (TIA) shortly after cannabis abuse... The urine analysis was positive for cannabis metabolites. There were no other abnormal findings in the rest of the meticulous and thorough study of all 3 patients, which leads to the conclusion that cannabis was the only risk factor responsible for the observed TIA, contradictory to other studies, which support that cannabis is a 'safe' drug."

However, it is clear that cannabinoids have a variety of cerebrovascular effects, increasing the blood supply to the brain[xlvi], and can protect against potentially fatal brain cell death following a stroke by reducing tumour necrosis factor, which causes self-destruction in exposed cells. The use of cannabinoids for treatment of brain damage arising from strokes is reaching an advanced stage of the licensing process, Job[xlvii] reported in 2000 "Dexanabinol is a non-psychotropic cannabinoid NMDA receptor antagonist under development by Pharmos Corp for the potential treatment of cerebral ischemia... cardiac failure, head injury and multiple sclerosis (MS)... it is in phase III trials for traumatic brain injury... Pharmos estimates that the worldwide market for dexanabinol in the treatment of severe head trauma may reach $1 billion per year" Leker et al[xlviii] investigated the effect of dexanabinol, a synthetic cannabinoid which is a NMDA antagonist, with antioxidant and anti-tumour necrosis factor alpha properties, on the levels of brain damage (infarct) following experimentally induced ischaemic strokes in rats, finding "Dexanabinol significantly decreased infarct volumes. It also significantly lowered TNFalpha levels in the ipsilateral hemisphere although not to the level of sham operated rats... In conclusion, dexanabinol may be a pluripotent cerebroprotective agent."

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Re: THC and altitude

by Flattlander » Tue Jan 11, 2011 8:31 pm

Dude, I'm too baked to read all these big words. Just kidding.

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Re: THC and altitude

by rasgoat » Tue Jan 11, 2011 10:44 pm

Are you talking about getting high while being high?

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Re: THC and altitude

by DukeJH » Wed Jan 12, 2011 8:14 pm

OK. I'll bite. I haven't been following the Ritalin thread though.

1) The cited studies only relate to cerebrovascular effects of cannibis use and do not address the cardiovascular effects. I would be curious to know how cannibis may affect the circulation in the extremities.

2) I doubt that the smoking of cannibis is conducive to increasing oxygen exchange in the lungs due to the potential damage caused by the other chemicals in the smoke. Therefore, I would expect that at high levels of performance, that VO2 might be reduced.

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Re: THC and altitude

by centrifuge » Wed Jan 12, 2011 9:24 pm

this got my brain working, so I looked up the effect THC has on bronchodilation. My thinking here is what happens when someone smokes Cannabis in the first place in regards to its assistance or restriction of O2's ability to reach your red blood cells in the first place. As DukeJH seems throws out there, what is the damage of the chemicals in the smoke, also, does the smoke itself cause the bronchial tubes to close which would also constrict oxygen.

Obviously without more time and access to the full journal articles to difficult to throw out too many conclusions, but the research I saw (Brittish Medical Association '97) (IACM-Bulletin of 12 November 2000; Calignano A, et al)(Del Bono N, Sconosciuto F, Del Bono L. '81) indicated that Marijuana assists with Bronchodilation, but it seems that the have been a couple of studies, including the above referenced article that talk about the counterproductive effects caused by the smoke. One other really interesting snippet I found from an article I just read seems to conclude that while THC does produce Bronchodilation, in doses over 200 micrograms, it actually has the opposite effect and has a constricting effect. In other words, in small doses it helps, but at a certain point, it has the opposite effect:

"Doses of A1-THC which are large enough to cause bronchodilatation when taken orally are invariably associated with psychological effects, and direct
bronchial administration of a smaller dose is, therefore, more appropriate. Smoking marijuana can cause bronchodilatation in asthmatic patients (Tashkin et al., 1974) and prevent experimentally- induced bronchospasm (Tashkin, Shapiro, Lee &
Harper, 1975) but the dose is difficult to control, the smoke irritates the airways and long-term use can impair lung function (Henderson, Tennant & Guerry,
1972). More recently, therefore, aerosolized A'-THC has been investigated. The smallest dose which has previously been shown to cause bronchodilatation
when given by aerosol to asthmatic patients is 200 micrograms
(Williams et al., 1976). Other workers have found larger doses given in this way to be effective, but not without psychological or local irritant effects (Tashkin, Reiss, Shapiro, Calvarese, Olsen & Lodge, 1977; Vachon, Robins & Gaensler, 1976)." Br. J. clin. Pharmac. (1978), 5, 523-525

it goes on to say:

"The optimal dose would appear to be 100 micrograms. The differences between 100 and 200 micrograms were small. We have found that doses higher than this commonly cause coughing and restrosternal discomfort, even in normal subjects, and this is more pronounced in asthmatics, in whom a transient increase in airways
obstruction may be found. It is possible that the local irritant effect of Al-THC even at 200 jig caused bronchoconstriction in all but the largest airways,
which opposed the direct bronchodilator activity of the drug, and this may have been responsible for the inversion of the dose response effect with respect to
FEV1." (Br. J. clin. Pharmac. (1978), 5, 523-525)

So I guess what that would infer is that if you took in too much THC (even as a tasty treat like a brownie so that you dont get any of the nasty stuff that comes with the smoke) that it could have the effect of constricting your bronchial tubes, thereby restricting the bodies ability to get O2 into the lungs in the first place.

Obviously this is very limited, and tons of research has been done that this doesn't even scratch the surface of, but I would wonder if the Cerebralvascular benefits citied in the OP's post would really do all that much good unless the dose was controlled enough to make sure that

a) the THC maintains its effects as a Bronchiodialator, thus allowing more o2 to reach the alveoli, thus giving it the opportunity to bond with the red blood cells and;

b) is not so high that it has the reverse effect, which would reduce the available o2 in your lungs.

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Re: THC and altitude

by DukeJH » Thu Jan 13, 2011 9:14 pm

Not to mention the phsycological or local irritant effects.

Based on my anecdotal evidence of folks who smoke this stuff, I don't know that I'd want to be on the hill with them after a "dose".

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Re: THC and altitude

by drpw » Mon Jan 17, 2011 4:43 pm

DukeJH wrote:Not to mention the phsycological or local irritant effects.

Based on my anecdotal evidence of folks who smoke this stuff, I don't know that I'd want to be on the hill with them after a "dose".

What about being tent bound for 24 hours during a storm? Titanium cookset drum circle!

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Re: THC and altitude

by etai101 » Mon Jan 17, 2011 7:51 pm

i would like to contribute my two cents on the topic no scientific basis just personal experience with the subject.

pot is great in the mountains especially in high altitude, reason-we all know it is not easy to go to sleep in high altitude even more before summit day or on the first night before a big alpine push.
its a combined feeling of anxiety anticipation and the daunting specter of having a crappy nights sleep
also the high altitude doesn't help its not real sleep its a half sleep, for all that pot helps allot!!!
there is no better way for getting acclimated than getting a good night high up.

another narcotic that helps a ton are coca leaves, in bolivia i liked to get a little baggie of leaves and put a bunch with my water.
coca foucases you and gives you an energy boost with out that energy gell/drink after effect that makes you crash once its through youre system.

"la hoja de coca es no droga"

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Re: THC and altitude

by LuminousAphid » Tue Feb 15, 2011 7:04 pm

All I know is that I love smoking in the mountains, and for me personally, taking a little smoke break gives me a sense of physical and mental relaxation that helps me make the right decisions. I find that I can think introspectively, not letting exterior, material desires for summits or views override my personal limits. There have also been many times when I thought I was done and would turn back, then sat down to have a smoke and ended up rejuvenated and ready for another 5 miles of strenuous hiking or scrambling.

I <3 THC either way, and it will always be part of my hiking and scrambling loadout. I can see where people would be wary in situations where reliance on another person might make getting high suspect, but I mostly go out alone or with people who can take care of themselves if I trip and take a stoned tumble off a cliff. I've only fallen once because of being high up high (slipped off the downhill side of a climber's path and flipped 360 head over heels into a tree), and I blame that on being a novice on both the trail and the pipe, at the time.

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Re: THC and altitude

by Blair » Wed Feb 16, 2011 3:22 am

I wonder who and where was the HIGHEST (in altitude) anyone has smoked out...

First Person to Smoke a Blunt on the BIG E!!!!

Who wants to start the expedition? A Jamaican team is in the works...

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Re: THC and altitude

by Tangeman » Sun May 15, 2011 11:59 pm

Reminds me of Eiger Dreams when they kept loading that guy up with weed in a snow cave on Denali, the worse his condition, the more they gave him.

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