FinaFlex G8 Review

FinaFlex G8

G8 is a sleep-aid/gh-elevator made by FinaFlex which makes use of some pretty potent sleep-inducing/enhancing substances…

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G8 is a sleep-aid/gh-elevator made by FinaFlex which makes use of some pretty potent sleep-inducing/enhancing substances…[Skip to the Bottom Line]


4-amino-3-phenyl-butyric acid, more commonly known as Phenibut, is a derivative of the inhibitory neurotransmitter, GABA. The primary role of GABA is to down-regulate the firing of neurons in the brain, effectively inducing relaxation. While supplemental GABA has difficulty crossing the blood-brain-barrier, Phenibut is able to with relative ease, thus making it an effective anxiolytic. While Phenibut stimulates GABA receptors, it has also been shown to increase Dopamine levels, which may offer a secondary mechanism of action for improving sleep quality.

Unfortunately, tolerance tends to build quickly with Phenibut and supplementation carries with it the risk of dependency. Just as many GABAergic drugs can cause severe and unpleasant withdrawal symptoms, so too can Phenibut so chronic supplementation is ill-advised. Common doses range from 100-500mg daily, though most manufacturers insist not to consume Phenibut more than a few days in a row and not to exceed 4000mg per week.

Ultimately, Phenibut can be quite effective as a sleep aid, but we recommend erring on the side of caution and not consuming it every night to avoid the risk of dependence. It’s unclear how much Phenibut is present in the G8 formula but given its listed first out of a 3000mg proprietary blend with three other ingredients, we suspect it contains a pretty hefty dose.


As discussed above, 4-aminobutanoic acid (GABA), is the primary inhibitory neurotransmitter in the brain, increased levels of which can have an anxiolytic/sedative-like effect. While increasing GABA levels can certainly result in sounder sleep, orally supplemented GABA does not easily cross the blood-brain-barrier, making it less effective than certain other substances (like Phenibut) for this purpose. Ultimately, while GABA certainly doesn’t lessen the efficacy of the G8 formula, it also doesn’t add to it very much and is likely an expendable ingredient in this case.


Arginine has become pervasive in the supplement industry for its alleged ability to increase Nitric Oxide levels which would theoretically enhance exercise. While we are highly skeptical of these claims (based on extremely conflicting research which has returned mostly negative results), Arginine has shown some efficacy towards increasing Growth Hormone levels, specifically during slow-wave sleep. A 1982 study, published in “Acta Endocrinologica”, found that subjects who consumed around 17g Arginine daily for one week experienced roughly a 60% increase in peak GH secretion during slow-wave sleep.

Two studies, one in 2006 from the “Journal of Applied Physiology” and one in 2008 from “Current Opinion in Clinical Nutrition & Metabolic Care”, have demonstrated that Arginine (doses of 5-9g) can increase GH release, though not as much as exercise alone. Both of these studies also noted that Arginine actually blunted exercise-induced GH spike when consumed prior. So, while we wouldn’t recommend pre-workout Arginine supplementation, it can effectively increase GH at other times, making it a practical addition to the G8 formula. However, the amount of Arginine present in G8 is questionable and based on its position (third) in the 3000mg proprietary blend, may not be enough to cause a meaningful GH increase (at least not compared to that seen in the above mentioned studies).


Glutamine has shown a lot of promise when it comes to fighting exercise induced immune system suppression. Our immune systems ultimately benefit from regular exercise, but in the short-term, exercise temporarily lowers our immune defenses, thus making us more susceptible to infection. This temporary compromise of the immune system has been proven to correlate with lower levels of glutamine. For this reason, it is suggested that increased uptake of glutamine may help keep the immune system strong post-exercise. In addition, lower glutamine levels have been recorded in over-trained athletes, suggesting that higher levels of glutamine may help to prevent overtraining. Ultimately, while Glutamine may not live up to all the hype, it certainly appears beneficial for exercise recovery. Unfortunately, the amount of Glutamine present in the G8 formula is far less than what would normally be recommended for immune support, so in the context of G8 we would consider Glutamine a bit unnecessary (though it can’t hurt either).


Phenethylamine, also known as Phenylethylamine, is primarily seen in stimulant-based pre-workouts and fat-burners because of its ability to stimulate the release of Catcholamine neurotransmitters (Dopamine, Serotonin, Noradrenaline, etc.). Interestingly, Phenylethylamine has a distinct affinity to Dopamine when compared to other neurotransmitters (100 times that of Serotonin), which is likely why FinaFlex has chosen to include it in the G8 formula. However, the effects of Phenylethylamine are dramatically hindered by the fact that it is rapidly metabolized by the enzyme Monoamine Oxidase, and generally requires co-ingestion of a Monoamine Oxidase Inhibitor (MAOI) for the effects to be noticeably apparent. Given that there are no MAOI’s present in the G8 formula, Phenylethylamine likely contributes very little to the formula. This is probably a good thing because, when paired with an MAOI, Phenylethylamine takes on stimulant-like properties which could potentially interfere with sleep. Ultimately, we’re not quite sure why Finaflex has chosen to include Phenylethylamine in the G8 formula.


Tyrosine is an amino acid which serves as a precursor to the neurotransmitters Dopamine and Noradrenaline. While commonly alleged to increase Dopamine and Noradrenaline levels, the real benefit of Tyrosine lies in its ability to restore these neurotransmitters when rapid depletion occurs (in the presence of an acute stressor). Tyrosine essentially forms a pool in the brain, and when depletion of Dopamine/Noradrenaline occurs, the pool is drawn from to restore them. For this reason, it is unlikely that supplemental Tyrosine would have any profound effect on sleep quality, except in individuals who are Tyrosine deficient (and thus Dopamine deficient). The direct effects of Tyrosine on sleep quality have never been investigated in a clinical environment.


Pikamilon (alternatively spelled ‘Picamilon’) is formed by combining Niacin (vitamin B3) and GABA (the primary inhibitory neurotransmitter in mammals). Pikamilon is able to effectively cross the blood-brain-barrier where it is converted into GABA. Since GABA is an inhibitory neurotransmitter (as opposed to excitatory) it may produce anxiolytic effects when levels are increased beyond normal. For this reason, Pikamilon is touted as an anxiolytic. However, it has also been demonstrated to increase cerebral blood flow in animals, due to its niacin component (niacin is a vasodilator). Despite a fair amount of efficacy demonstrated in animal studies for both cerebral vasodilation and as an anxiolytic, human studies remain scarce. This is likely because there are better (pharmaceutical grade) anxiolytic compounds as well as cerebral vasodilators. Ultimately, Pikamilon may slightly increase the presence of GABA in the brain in a similar, but much less potent, manner as Phenibut.


5-HTP is the direct precursor to the “happy” neurotransmitter Serotonin, which plays a vital role in sleep. Though the relationship between 5-HTP supplementation and sleep quality remains under-researched, a 2010 study found that a combination of 5-HTP and GABA was able to enhance sleep quality in humans. Unfortunately, this study was confounded with the inclusion of other ingredients which may have altered the results. That being said, there is a litany of subjective, anecdotal reports of 5-HTP improving sleep quality as well as duration and latency (time it takes to fall asleep). While we wouldn’t regard these reports as facts, they certainly lend credibility to the already established notion that 5-HTP may improve certain aspects of sleep. It is unclear how much 5-HTP is present in the G8 formula, but common doses range from 50-200mg so we’d estimate somewhere in that range.


G8 contains several effective sleep-aids as well as some questionable (perhaps not so effective) sleep-aids, the combination of which result in one of the most potent sleep formulas we’ve come across. To put it simply, G8 will put you out and will probably keep you out (depending on individual sensitivities) for the whole night. However, because of the use of Phenibut, we wouldn’t recommend consuming G8 nightly and would instead suggest short cycles (such as 3 nights on 2 nights off, or something like that). Dependence is always an issue when dealing with Phenibut, and the only way to avoid it completely is not to use it all the time. Furthermore, certain individuals may experience next-day grogginess, which cannot be entirely attributed to any particular ingredient. That being said, if getting to sleep quickly and staying asleep is the goal, G8 is one of the best formulas we’ve come across. Just be careful with this stuff!

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