60mg kavalactones, which is good, since it’s a dose that shouldn’t negatively impact reaction time or cognition or anything like that. One study even noted that 90mg kavalactones improved some aspects of cognition (and mood, but that’s more expected I suppose). A different study with 36mg/day kavalactones for 7 days noted no effects (good or bad) on reaction time or cognitive performance, but did find that it made a stressful test seem less stressful relative to placebo. Another study noted that 180mg kavalactones didn’t impair simulated driving performance, and yet another study found 450mg kavalactones did increase the extent of body sway similar to what alcohol does. So you definitely don’t want to overdo it.
It also seems to be non-addictive, at least in moderation:
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).
However, without knowing if it’s noble kava or not, it’s hard to say if it’ll have any effects on the liver. Granted, it’s not a very high dose either way, but a lot of research seems to suggest that noble kava is much safer for the liver
See here for more info on kava studies, including various doses and their effects, addictive potential, effects on the liver, etc: