Caffeine + L-Theanine: Since caffeine can produce unwanted side effects in high amounts (such as jitteriness and headaches), most people, and especially “slow caffeine oxidizers” find that by adding L-Theanine to a caffeine source such as coffee, any negative side effects of caffeine can be controlled. Caffeine and L-Theanine in combination have been researched and proven to boost concentration, attention, and energy while reducing anxiety. For this stack, use a ratio of four parts L-Theanine to one part caffeine, such as 400 milligrams of L-Theanine along with 100 milligrams of caffeine. You may want to start out with a smaller dose such as 200 milligrams of L-Theanine and 50 milligrams of caffeine and work your way up to find the best dose for you (the average cup of coffee has about 100mg of caffeine).
Theanine can also be combined with caffeine as both of them work in synergy to increase memory, reaction time, mental endurance, and memory. The best part about Theanine is that it free of side effects and is easily available in the form of capsules.  A natural option would be to use a good green tea brand which constitutes of tea grown in the shade, because then Theanine would be abundantly present in it.
We did note a significant warning with this product, namely that the caffeine it contains may cause a negative impact, mainly that some users may experience the jitters. Their dosage suggests that one can take up to 6 pills a day, which we felt was too many. These issues made us a little wary of the product, even though they seem to know the right ingredients to include.
This doesn’t fit the U-curve so well: while 60mg is substantially negative as one would extrapolate from 30mg being ~0, 48mg is actually better than 15mg. But we bought the estimates of 48mg/60mg at a steep price - we ignore the influence of magnesium which we know influences the data a great deal. And the higher doses were added towards the end, so may be influenced by the magnesium starting/stopping. Another fix for the missingness is to impute the missing data. In this case, we might argue that the placebo days of the magnesium experiment were identical to taking no magnesium at all and so we can classify each NA as a placebo day, and rerun the desired analysis:

Tyrosine ( is an amino acid; people on the forums (as well as Wikipedia) suggest that it helps with energy and coping with stress. I ordered 4oz (bought from Smart Powders) to try it out, and I began taking 1g with my usual caffeine+piracetam+choline mix. It does not dissolve easily in hot water, and is very chalky and not especially tasty. I have not noticed any particular effects from it.
One reason I like modafinil is that it enhances dopamine release, but it binds to your dopamine receptors differently than addictive substances like cocaine and amphetamines do, which may be part of the reason modafinil shares many of the benefits of other stimulants but doesn’t cause addiction or withdrawal symptoms. [3] [4] It does increase focus, problem-solving abilities, and wakefulness, but it is not in the same class of drugs as Adderall, and it is not a classical stimulant. Modafinil is off of patent, so you can get it generically, or order it from India. It’s a prescription drug, so you need to talk to a physician.
Such competitive anxieties are already being felt in the workplace. Recently an advice column in Wired featured a question from a reader worried about "a rising star at the firm" who was "using unprescribed modafinil to work crazy hours. Our boss has started getting on my case for not being as productive." And on internet forums such as ImmInst (Immortality Institute), whose members share a nerdy passion for tweaking their cognitive function through drugs and supplements, people trade advice about dosages and "stacks" - improvised combinations - of neuroenhancers ("Cut a tablet into fourths and took 25mg every four hours, four times today, and had a great and productive day - with no side-effects"). In one recent post a 52-year-old - who was working full time, studying for an advanced degree at night and "married, etc" - wrote that after experimenting with modafinil he had settled on two daily doses of 100mg each. He believed that he was "performing a little better", adding: "I also feel slightly more animated when in discussion."
One claim was partially verified in passing by Eliezer Yudkowsky (Supplementing potassium (citrate) hasn’t helped me much, but works dramatically for Anna, Kevin, and Vassar…About the same as drinking a cup of coffee - i.e., it works as a perker-upper, somehow. I’m not sure, since it doesn’t do anything for me except possibly mitigate foot cramps.)

My worry about the MP variable is that, plausible or not, it does seem relatively weak against manipulation; other variables I could look at, like arbtt window-tracking of how I spend my computer time, # or size of edits to my files, or spaced repetition performance, would be harder to manipulate. If it’s all due to MP, then if I remove the MP and LLLT variables, and summarize all the other variables with factor analysis into 2 or 3 variables, then I should see no increases in them when I put LLLT back in and look for a correlation between the factors & LLLT with a multivariate regression.
Either prescription or illegal, daily use of testosterone would not be cheap. On the other hand, if I am one of the people for whom testosterone works very well, it would be even more valuable than modafinil, in which case it is well worth even arduous experimenting. Since I am on the fence on whether it would help, this suggests the value of information is high.
L-Glutamine- One Of The 13 Essential Ingredients In Brain Fuel Plus… Perhaps the best fitting ingredient in our product’s name, L-Glutamine is the only compound besides blood sugar that can both cross the blood brain barrier AND be used by the brain for energy, which is why it is commonly called “brain fuel.” In fact L-Glutamine is involved in more metabolic processes than any other amino acid in the entire body. It is shown to promote mental alertness, improve mood and memory, and help with depression and irritability. It has even been shown to improve IQ.

But before you go lock yourself in a dark, quiet room in order to prevent this overburden on your brain, you should know that there are scientifically researched compounds designed to amplify cognitive function and help your brain deal with this excess load, or simply get you through a period of sleep deprivation, increased creativity or work demands, the need to pull an all-nighter or an intense bout of work or study.

With a lack of reviews and a formulation containing some questionable ingredients that we could not find to benefit consumers, together with the possibility of the product being sub-standard, we placed this product in our # 4 ranking. Its redeeming features however, include the fact that they use all-natural ingredients plus, the price is cheap, if you are into taking a risk about the quality of the product.
We felt that NeuroFuse was pretty much on par with other similar products. We were happy to see that this supplier offers a money-back guarantee. However, we didn't really like the 14-day trial offer they promote. On the surface it seems good, however, our experience on these matters suggests that if consumers are not happy with the product, cancelling subscriptions can be a nightmare. We much prefer a simple clear money-back guarantee, it's safer for consumers.
“We stumbled upon fasting as a way to optimize cognition and make yourself into a more efficient human being,” says Manuel Lam, an internal medicine physician who advises Nootrobox on clinical issues. He and members of the company’s executive team have implanted glucose monitors in their arms — not because they fear diabetes but because they wish to track the real-time effect of the foods they eat.
Adderall is a mix of 4 amphetamine salts (FDA adverse events), and not much better than the others (but perhaps less addictive); as such, like caffeine or methamphetamine, it is not strictly a nootropic but a cognitive enhancer and can be tricky to use right (for how one should use stimulants, see How To Take Ritalin Correctly). I ordered 10x10mg Adderall IR off Silk Road (Wikipedia). On the 4th day after confirmation from seller, the package arrived. It was a harmless looking little padded mailer. Adderall as promised: 10 blue pills with markings, in a double ziplock baggy (reasonable, it’s not cocaine or anything). They matched pretty much exactly the descriptions of the generic I had found online. (Surprisingly, apparently both the brand name and the generic are manufactured by the same pharmacorp.)
Gamma-aminobutyric acid, also known as GABA, naturally produced in the brain from glutamate, is a neurotransmitter that helps in the communication between the nervous system and brain. The main function of this Nootropic is to reduce the unnecessary activity of the nerve cells and helps calm the brain. . Thus it helps improve various conditions, like stress, anxiety and depression by decreasing the beta brain waves and increasing the alpha brain waves.  As a result, cognitive abilities like memory power, attention, and alertness also improve. GABA helps drug addicts recover from addiction by  normalizing the brain’s GABA receptors which reduce anxiety and craving levels in the absence of addictive substances.
Jump up ^ EFSA Panel on Dietetic Products, Nutrition and Allergies; European Food Safety Authority (EFSA), Parma, Italy (2011). "Scientific Opinion on the substantiation of health claims related to L-theanine from Camellia sinensis (L.) Kuntze (tea) and improvement of cognitive function (ID 1104, 1222, 1600, 1601, 1707, 1935, 2004, 2005), alleviation of psychological stress (ID 1598, 1601), maintenance of normal sleep (ID 1222, 1737, 2004) and reduction of menstrual discomfort (ID 1599) pursuant to Article 13(1) of Regulation (EC) No 1924/2006". EFSA Journal. 9 (6): 2238. doi:10.2903/j.efsa.2011.2238.