Alright, let's go

[kl.NDG]

Hum Psychopharmacol. 2012 May;27(3):262-9. doi: 10.1002/hup.2216. Epub 2012 Feb 7.The acute effects of kava and oxazepam on anxiety, mood, neurocognition; and genetic correlates: a randomized, placebo-controlled, double-blind study.Sarris J, Scholey A, Schweitzer I, Bousman C, Laporte E, Ng C, Murray G, Stough C.SourceThe University of Melbourne, Department of Psychiatry, 2 Salisbury St., Richmond, Melbourne, Australia. [email protected]: Kava
(Piper methysticum) is a psychotropic plant medicine with history of
cultural and medicinal use. We conducted a study comparing the acute
neurocognitive, anxiolytic, and thymoleptic effects of a medicinal dose
of kava to a
benzodiazepine and explored for the first time specific genetic
polymorphisms, which may affect the psychotropic activity of
phytomedicines or benzodiazepines.METHODS: Twenty-two moderately anxious adults aged between 18 and 65 years were randomized to receive an acute dose of kava (180 mg of kavalactones), oxazepam (30 mg), and placebo 1 week apart in a crossover design trial.RESULTS: After exposure to cognitive tasks, a significant interaction was revealed between conditions on State-Trait Anxiety Inventory-State anxiety (p = 0.046, partial ŋ² = 0.14). In the oxazepam condition, there was a significant reduction in anxiety (p = 0.035), whereas there was no change in anxiety in the kava condition, and there was an increase in anxiety in the placebo condition. An increase in Bond-Lader "calmness" (p = 0.002) also occurred for the oxazepam condition. Kava
was found to have no negative effect on cognition, whereas a reduction
in alertness (p < 0.001) occurred in the oxazepam condition. Genetic
analyses provide tentative evidence that noradrenaline (SLC6A2)
transporter polymorphisms may have an effect on response to kava.CONCLUSION: Acute "medicinal level" doses of this particular kava
cultivar in naive users do not provide anxiolytic activity, although
the phytomedicine also appears to have no negative effects on cognition

This study is bad, bad bad. Did no one inform them of reverse tolerance?acute dosing probably won't work in the vast majority, this study highlights the biggest drawback of kava, Reverse tolerance. Anxiolysis from all the data takes about two weeks of steady dosing to achieve.

 

[kl.NDG]

I wrote a small novel on this study and deleted it, perhaps to krunk?



Phytother Res. 2013 Jan 24. doi: 10.1002/ptr.4916. [Epub ahead of print]

Kava for the Treatment of Generalized Anxiety Disorder RCT: Analysis of Adverse Reactions, Liver Function, Addiction, and Sexual Effects.

Sarris J, Stough C, Teschke R, Wahid Z, Bousman C, Murray G, Savage K, Mouatt P, Ng C, Schweitzer I.

Source



Department of Psychiatry, The University of Melbourne, Victoria, Australia; Swinburne University of Technology, Centre for Human Psychopharmacology, Victoria, Australia; NICM Collaborative Centre for Neurocognition, Victoria, Australia.

Abstract



Presently, little is known about a number issues concerning kava (Piper methysticum), including (i) whether kava has any withdrawal or addictive effects; (ii) if genetic polymorphisms of the cytochrome (CYP) P450 2D6 liver enzyme moderates any potential adverse effects; and (iii) if medicinal application of kava has any negative or beneficial effect on sexual function and experience. The study design was a 6-week, double-blind, randomized controlled trial (n = 75) involving chronic administration of kava (one tablet of kava twice per day; 120 mg of kavalactones per day, titrated in non-response to two tablets of kava twice per day; 240 mg of kavalactones) or placebo for participants with generalized anxiety disorder. Results showed no significant differences across groups for liver function tests, nor were there any significant adverse reactions that could be attributed to kava. No differences in withdrawal or addiction were found between groups. Interesting, kava significantly increased female's sexual drive compared to placebo (p = 0.040) on a sub-domain of the Arizona Sexual Experience Scale (ASEX), with no negative effects seen in males. Further, it was found that there was a highly significant correlation between ASEX reduction (improved sexual function and performance) and anxiety reduction in the whole sample. Copyright © 2013 John Wiley & Sons, Ltd.

 

[Prince Philip]

Yeah... they needed to do a LONG RANGE, LONGITUDINAL study.



With BASS DROPS being randomly controlled, with a double-blind (or, in this case study, double-deaf). 1/2 of the participants receiving a several months of high-grade traditionally prepared kava and top-40 music, the other 1/2 receiving high-grade kava with their choice of dubstep with epic bass drops, metal with epic base drops, or hardcore rave with epic bass drops.

 

[JonT]

To start from the beginning, the existence of RT needs to be proven in a study. Many of us here are certain it exists, but you've got to build up this knowledge over time in science.

 

[August West]

Honestly, I would love to know scientifically why some people react positively the first time versus others who have to partake several weeks before a reaction is had. I wonder if more receptor sites are created after a period of usage, sort of like how nicotine or other substances act.

 

[Buddhacide]

Honestly, I would love to know scientifically why some people react positively the first time versus others who have to partake several weeks before a reaction is had. I wonder if more receptor sites are created after a period of usage, sort of like how nicotine or other substances act.

I honestly believe its a matter of amount and quality of the kava. I personally am skeptical of reverse tolerance. I think most people just dont take enough. I have given strong doses of nambawan and paradise awa to several people that had never taken kava before and nobody ever complained it didnt work. I never experienced it either, I just didnt know what I was looking for until I did an isa that really kicked my ass. at the time I just found the others crappy by comparison. Now I have a more refined taste for it, and can appreciate a less intense experience in its own right. But I dont think my neurochemistry had to adapt in the way people assume with RT. Kava just didnt seem like it was worth the effort until I found one that really bludgeoned me.

I also dont know exactly how a "reverse tolerance" would work physiologically. Tolerance is when your body stops producing, say a neurotransmitter, as a ratelimiting factor based on the presence of exogenous substances. Ie, your body sees there is a lot of extra serotonin floating around and therefore stops creating its own. Eventually the brain changes physiologically to accommodate the presence of the drug (receptors re-regulate etc....) This has the effect of both making you require the drug to be otherwise normal, and reducing the amount of efficacy the drug has to attain added effects (the high). Its been a while since I studied neuroscience, but I dont recall learning anything that would describe "reverse tolerance". 

NDG, maybe you know something about this?

Edit: Even in this wiki article it refers to a process much different (seemingly) than how users here refer to "RT" - the succession of unwanted side effects not the outright effects of the drug itself.

http://en.wikipedia.org/wiki/Reverse_tolerance