Here’s some interesting research on the cognitive effects of kava. Kava can be abused, of course, and you can get intoxicated if you take too much, as I will discuss, but using a standardized extract seems like a good way to ensure you’re getting a sufficient dose without taking too much, assuming you don’t take too much of the extract, of course. Anyway:
300mg of kava extract (containing 90mg kavapyrones) given to kava-naive healthy volunteers (aged 18-53, average age 24.3 years):
But that’s not the only study to note benefits:
This study noted no differences (which means no decrease, but also no increase) in reaction time or number of correct responses with 120mg of a 30% kavapyrone extract (36mg kavapyrones) for 7 days, but it did reduce how stressful subjects found the stress task to be relative to placebo.
In a third study, 200mg of a 70% kavalactone extract taken 3x per day for 5 days (420mg/day kavalactones) lead to a nonsignificant increase in the number of correct responses in a continuous word recognition task.
A dose of kava containing 180mg kavalactones was given to adults aged 18-65 before a driving simulation:
The results indicate that a medicinal dose of kava containing 180 mg of kavalactones does not impair driving ability, whereas 30 mg of oxazepam shows some impairment. Research assessing larger recreational doses of kava on driving ability should now be conducted.
Also referenced in the above study are these studies:
So you don’t want to go too high with the dose. Studies showing some sort of benefits used:
an acute dose of 90mg kavapyrones
7 days of 36mg/day kavapyrones
And a study that showed no negative effects with an acute dose of 180mg kavalactones, and another showing no negative effects of 300mg/day kava for 15 days (with no mention of how, if at all, the daily dose was split)
But then we see that a single dose of 450mg kavalactones lead to increased body sway similar to alcohol intoxication, so don’t overdo it. The study that used 420mg/day kavalactones and noted slight/nonsignificant cognitive benefits split the dose into 3 servings per day, which likely was why no intoxication was noted; a single serving was only 140mg, which is much less than the 450mg that lead to intoxication-like effects.
Disclaimer: I do not advise driving after taking kava. None of this is medical or legal advice. I’m not a doctor or a lawyer.
Also, regarding the claims that kava is addicting:
Kava may even HELP with addiction:
[quote]In another attack on kava following the rise in popularity of kava bars in the USA, Rodriguez (2016) suggests that: ‘when someone walks into a Kava bar, the last thing they are thinking of is going away to rehab in the next few months.’ He adds that the ‘regular use of Kava can lead to a chemical withdrawal syndrome, with some developing a physical dependence very quickly.’ This however has been denied by long-term heavy kava users who report that periods of kava abstinence, as part of cultural observance, are common, with users reporting or showing no addictive symptoms during these times. Such commentary aligns with a gathering body of research and ethnographic comment, showing that kava use, even at high volumes and regular use, is not generally addictive (Bilia et al., 2001; Connor et al., 2001; Geier and Konstantinowicz, 2004; Keltner and Folkes, 2005; MediHerb, 2004; Scherer, 1998; Thompson et al., 2004). Drawing on earlier research, Aporosa (2014) summarizes by suggesting that ‘if the label “addiction” is to be applied to yaqona [kava], I would hesitantly use “socially addictive” in the sense that it has been habituated to most aspects of Fijian socialization’ (147).
Despite kava being a daily practice in many Pasifika communities (Aporosa, 2019b), assertions that kava is non-addictive is well documented (as shown in the lengthy reference list above). Additionally, Sarris et al. (2013) undertook a double-blind, placebo comparison aimed at kava withdrawal and addiction, reporting ‘no addictive qualities or withdrawal issues’ (1727). Admittedly, the doses administered (120 mg titrated to 240 mg of kavalactones per day per participant over six weeks) are considerably less than those consumed by traditional and recreational kava drinkers (Sarris et al., 2013: 1727) – amounts that can be more than 30 times those used in the Sarris et al.’s study (Aporosa, 2017b).[/quote]
Liver injury caused by medicinal and traditional kava extracts as a consequence of inappropriate kava raw material has undermined consumer confidence in modern herbal medicine. A current approach is being made to overcome lack of standards and to suggest criteria for good kava quality, both in Western countries and in the South Pacific Islands.
The critical next step forward in assisting the Pacific Island people with the re-introduction of their valuable export commodity and cultural icon, is to go back to basics, back to using water extracts of peeled noble kava rhizomes and roots.
Kava-induced liver injury has been demonstrated in a few patients worldwide and appears to be caused by inappropriate quality of the kava raw material. When cases of liver disease in connection with the use of kava emerged, this was an unexpected and challenging event considering the long tradition of safe kava use. In order to prevent kava hepatotoxicity in future, a set of quality specifications as standard is essential for the preparation not only of kava drugs and kava dietary supplements in the Western world but also for traditional kava drinks in the South Pacific Islands. For all these purposes a uniform approach is required, using water based extracts from the peeled rhizomes and roots of a noble cultivar such as Borogu with at least 5 years of age at the time of harvest.
We thereby propose a six-point kava solution plan: (1) use of a noble kava cultivar such as Borogu, at least 5 years old at time of harvest, (2) use of peeled and dried rhizomes and roots, (3) aqueous extraction, (4) dosage recommendation of ≤250mg kavalactones per day (for medicinal use), (5) systematic rigorous future research, and (6) a Pan Pacific quality control system enforced by strict policing.
TL;DR: Use Noble kava, and don’t overdo it with how much you use.