The controversial Russian nootropic phenibut is becoming more widely known and used but is it safe? This is more of an open-ended question as it primarily depends on the purpose and the manner they are using it. Phenibut’s controversy extends beyond its safety, there are those who argue it isn’t actually a nootropic at all. In actuality, the nootropic range for phenibut is a rather small therapeutic window around 250-500mg is about the maximum for improving focus. The rule of thumb is once you’ve taken enough to induce any amount of muscular relaxation the nootropic effects will be diminished. Anything above those levels it becomes sedative, highly anxiolytic but there are concerns you should be aware of if you’re considering using phenibut.
Phenibut found it’s ways to the mainstream recently. It’s even available at some Wal-Marts. There are some considerations you bear in mind if you’re planning on using phenibut for anxiety, sleep, focus or body building.
Phenibut, like picamilon (an altered b-vitamin fused to a more bioavailable form of GABA) was developed in the 1960’s by Russian scientists as a focusing agent that would also provide anxiety and stress relief. Stimulating focusing agents can have a deleterious effect if over-used so phenibut and picamilon were a work-around allowing a calming focus, akin to a “super-theanine.” Phenibut came standard in the Cosmonaut’s medical kit in case of emergency. In the proper dosages it should assist focus while providing some anxiety support without resulting in the kind of inebriation that can result with prescription anti-anxiety drugs or alcohol (which also operate on GABA, the brain’s primary inhibitory neurotransmitter. 
Taken in the proper doses, phenibut side effects are uncommon. At threshold to moderate doses the worst you should experience is some lightheadedness or possibly nausea, headaches in some rare cases. Anecdotal evidence suggests some users may experience some numbness in the limbs or a tingling feeling. There are also reports of vivid dreams which may be connected to phenibut’s affect on sleep cycle. Many users find phenibut results in deep, healthy sleep unlike many other over-the-counter or prescription sleep aids. Be advised that overdoing it may result in a sluggishness upon waking.
Phenibut withdrawal and addiction
Phenibut does pose potential addiction and withdrawal potential if not used as directed. The max dosage should be between 500 and 1500mg daily and it should also be cycled. So long as you don’t use phenibut more than 2-3 times per week and stick to the recommended dosage the potential for any withdrawal or addiction issues is very slight. Some people have attempted to use phenibut for recreational uses which can result in a sort of “lucid drunkenness” as it’s described by some. As with many substances, the law of diminishing returns is something to consider. Using it regularly, especially at higher doses, will result in your body developing a tolerance. Phenibut takes a while to take effect as well, up to three hours before full effects are felt. It also possesses a long half-life so it’s important not to redose just because you don’t feel effects instantly.
For those who are taking phenibut for anxiety or sleep support, it’s a good thing to remember that in cases of phenibut abuse and addiction insomnia and anxiety have been reported as side effects. This is an unfortunate side effect of most potent GABAergic drugs. If you regularly take phenibut and begin to develop a tolerance you may find it loses its effectiveness. Taking larger amounts at this point will only increase tolerance and addiction potential. If you’re looking for anxiety support it’s a good idea to have several aids and switch out regularly. Bacopa, theanine and ashwagandha are better for regular usage than phenibut.
Phenibut and alcohol dangers
Do NOT mix phenibut with alcohol. Both are GABAergics. GABA receptor s assist in neuronal transmission by inhibiting the neuron from firing. Overstimulation can lead to brain cell death due to excitotoxicity but mixing depressants is also potentially neurotoxic. Combining phenibut with alcohol can dangerously increase the debilitating effects. Overdose from either substance is more likely when they are combined. Side effects such as memory impairment, dizziness, inebriation, issues with balance and motor control and most dangerously risk of reduced heartrate and difficulty breathing that can result in total unconsciousness or “blackout” periods.
As mentioned previously, phenibut has a long half-life so it has a long duration of effects and after-effects. Its recommended to wait at least a full day before ingesting alcohol after dosing phenibut. Alcohol has a much shorter half- life, but you should still wait several hours after drinking before attempting to ingest any phenibut. 
As long as you cycle its usage and stick to the recommended daily dosage of no more than 500-1500mg, potential for overdose should not be an issue but since everybody and every BODY is different it’s a good idea with any new substance to test at the lower window. Minimum effective dosing is a good idea not only for your wallet but for your body and brain.
Phenibut, when used as directed and sparingly, is not only a focusing agent, but is also an anamnesic compound that has some neuroprotective and anti-hypoxic activity. It can even be a boon to body builders as it seems to support the release of endogenous growth hormone.
Remember to check with your personal care practitioner before starting any new diet, exercise or supplement regimen. This is especially important if you’re currently under a doctor’s care for any pre-existing condition or take over the counter or prescription drugs. Phenibut will increase the effects of any GABAergics, especially anti-anxiety drugs like benzodiazepines, so if you’re prescribed drugs like Xanax or valium phenibut be sure to exercise caution and dose below the recommended amount.