I've used sulbutiamine + caffeine (sold together in a "secret proprietary format" by Biotest and called "Spike." Note: it is NOT the same as their energy drink, also called "Spike." The drink is just caffeine, taurine, and like 25,000% of one of the B vitamins. The pill is sulbutiamine + caffeine).
I noticed from it increased concentration and a bit of a desire to do work. Usually I used it if I didn't get enough sleep the night before, I'd pop a pill in the morning and within an hour I was feeling as if I had gotten a good night of sleep.
I've also used Phenibut, which I don't know if that's considered a nootropic or not, but it was a phenomenal social lubricant (the reason I used it). It's also a potentiator of alcohol, so if you drink, you won't need more than 2 or 3 drinks the entire night... not that you'd want to drink much anyway... you're already too busy being happy and social on Phenibut.
A few warnings about Phenibut, tho:
1. It takes a few hours to kick in, so don't take it, and then when you don't feel anything in 20 minutes, don't take more thinking your initial dose wasn't big enough. It was. You just have to wait 3-4 hours. The effect lasts for 8-12 hours and then comes down nicely. There's no crash.
2 . Start SMALL and work your doses up. It's better to underdose and end up not getting any effects than to take too much and have the flu for the next 24-48 hours. I got 500mg pills (I think) and I was opening them, taking half the dose and putting it into an empty capsule, so I was only taking 1/2 of the standard pill size. My reason for doing this was:
3. People report that Phenibut is a "chase the dragon" drug in that your first use is always the best (I didn't have that experience, however, as my first use gave me a slight headache that lasted for the entire time in addition to the social lubricant effects, but the headache never returned with subsequent usage).
4. DO NOT USE IT LONG TERM, OR OFTEN. You will build tolerance FAST, and withdrawals will fuck you up when you stop. We're talking benzo-type withdrawals. Anxiety. Panic. Vomiting. Chills. Inability to get out of bed. Uncontrollable shaking. Search online. Read about the guy who used it daily for 6 months and then stopped. Read about the people who took too big of doses and had flu-like symptoms for days afterward.
For that reason, I would never use it more than twice a month (extremely conservative usage, some people say twice a week is fine, but I like to be very cautious).
Supposedly in Russia it's used long term as an anxiolytic (anti-anxiety drug) and a sleep aid. FUCK THAT. You cannot use it regularly or long term without fucking yourself up so I have no idea why doctors would use it long term with patients in Russia.
But if you're responsible with it, you use occasional, small doses, it can be wonderful, especially for an introvert like me I'd take a small dose at 2pm, meet up with some friends at 5pm (feel it starting to kick in), we'd have dinner, go out to a bar, and I would be feeling so social and happy and, while I'm normally introverted and I'm told I give off "elitist" vibes, I actually wanted to talk to people. Absolutely incredible. Imagine feeling like you're in the zone and instead of thinking everyone is a stupid idiot, you actually want to talk to them, and you enjoy doing so. And the whole time you have this wonderful, warm, happy feeling inside.
I definitely recommend it (provided you do your research first). There's an article on wikipedia about Phenibut, too.
Ordered some in tablets, don't want none of that powder shit, hopefully it will be the same.
