After a month of testing nootropics, I’m not ready to commit to them permanently. They’re simply too untested, and while “move fast and break things” might be a good approach to building software, it’s not what I want for my brain. Still, I think we’ll likely hear more about nootropics, especially as recreational users of more powerful prescription drugs like Adderall and modafinil look for less harsh alternatives. Sometimes, when you’re working, you don’t want to put your brain on jet fuel—a little unleaded gas will do. And for those moments, nootropics could be a fertile testing ground for the intrepid body-hacker.
There are plenty of brain supplements on the market, but none with the same combinations of potent and promising ingredients. If you want to maximize your ability to excel  – at everything you do – your brain must be firing on all cylinders – all day, every day. You must protect and preserve your brain function, as it will diminish – it’s the reality of being human.
Pomegranate juice. Pomegranate juice (you can eat the fruit itself but with its many tiny seeds, it's not nearly as convenient) offers potent antioxidant benefits, says Kulze, which protect the brain from the damage of free radicals. "Probably no part of the body is more sensitive to the damage from free radicals as the brain," says board-certified neurologist David Perlmutter, MD, author of The Better Brain Book. Citrus fruits and colorful vegetables are also high on Perlmutter's list of "brainy" foods because of their antioxidant properties -- "the more colorful the better," he says. Because pomegranate juice has added sugar (to counteract its natural tartness), you don't want to go overboard, says Kulze; she recommends approximately 2 ounces a day, diluted with spring water or seltzer.
Kratom (Erowid, Reddit) is a tree leaf from Southeast Asia; it’s addictive to some degree (like caffeine and nicotine), and so it is regulated/banned in Thailand, Malaysia, Myanmar, and Bhutan among others - but not the USA. (One might think that kratom’s common use there indicates how very addictive it must be, except it literally grows on trees so it can’t be too hard to get.) Kratom is not particularly well-studied (and what has been studied is not necessarily relevant - I’m not addicted to any opiates!), and it suffers the usual herbal problem of being an endlessly variable food product and not a specific chemical with the fun risks of perhaps being poisonous, but in my reading it doesn’t seem to be particularly dangerous or have serious side-effects.
One of the most popular legal stimulants in the world, nicotine is often conflated with the harmful effects of tobacco; considered on its own, it has performance & possibly health benefits. Nicotine is widely available at moderate prices as long-acting nicotine patches, gums, lozenges, and suspended in water for vaping. While intended for smoking cessation, there is no reason one cannot use a nicotine patch or nicotine gum for its stimulant effects.
Microdosing with Iboga: Native to the rainforests in Central Africa, Iboga is an evergreen shrub, with high concentrations found in the root bark. It has a rich history amongst practitioners in the indigenous Bwiti religion in Africa and has recently found its way into Western practices, primarily for extremely effective therapy for drug addictions, but also for physical energy, cognitive performance in smaller microdoses, and a surge in positive emotions (See additional studies here and here.).  To microdose with Iboga, you will want to find it in tincture or root bark form (the root bark form is typically encapsulated). If using a tincture, find a source that has the root bark extracted into its purest form, combined with Iboga alkaloids, which keeps the full spectrum of the plant untouched. Just a single drop of an Iboga tincture equates to about 0.5 milligrams and suffices as a microdose. For the root bark of Iboga, a dose of 300-500 milligrams is also an effective dose. I’ve personally found Iboga to be most useful prior to a workout or an effort that combines both brain and body demands, such as tennis or basketball – but it makes you hyperactive and jittery if taken prior to a day of desk work. This makes sense when you consider that African tribes traditionally whipped themselves into a frenzied pre-battle state on Iboga.
That first night, I had severe trouble sleeping, falling asleep in 30 minutes rather than my usual 19.6±11.9, waking up 12 times (5.9±3.4), and spending ~90 minutes awake (18.1±16.2), and naturally I felt unrested the next day; I initially assumed it was because I had left a fan on (moving air keeps me awake) but the new potassium is also a possible culprit. When I asked, Kevin said:

The effect? 3 or 4 weeks later, I’m not sure. When I began putting all of my nootropic powders into pill-form, I put half a lithium pill in each, and nevertheless ran out of lithium fairly quickly (3kg of piracetam makes for >4000 OO-size pills); those capsules were buried at the bottom of the bucket under lithium-less pills. So I suddenly went cold-turkey on lithium. Reflecting on the past 2 weeks, I seem to have been less optimistic and productive, with items now lingering on my To-Do list which I didn’t expect to. An effect? Possibly.
A record of nootropics I have tried, with thoughts about which ones worked and did not work for me. These anecdotes should be considered only as anecdotes, and one’s efforts with nootropics a hobby to put only limited amounts of time into due to the inherent limits of drugs as a force-multiplier compared to other things like programming1; for an ironic counterpoint, I suggest the reader listen to a video of Jonathan Coulton’s I Feel Fantastic while reading.
The nootropic sulbutiamine, of the synthetic B-vitamin-derived nootropics family, is generally considered a low-risk supplement; however, some users have reported that the supplement has addictive qualities. While there is no firm evidence of sulbutiamine addiction, the risk may increase at high dosages. For instance, users who consume this supplement for 10 consecutive days may experience withdrawal for two to five days. There are also increased risks when sulbutiamine is taken with antipsychotic medications.[8]
As it happens, these are areas I am distinctly lacking in. When I first began reading about testosterone I had no particular reason to think it might be an issue for me, but it increasingly sounded plausible, an aunt independently suggested I might be deficient, a biological uncle turned out to be severely deficient with levels around 90 ng/dl (where the normal range for 20-49yo males is 249-839), and finally my blood test in August 2013 revealed that my actual level was 305 ng/dl; inasmuch as I was 25 and not 49, this is a tad low.

The main concern with pharmaceutical drugs is adverse effects, which also apply to nootropics with undefined effects. Long-term safety evidence is typically unavailable for nootropics.[13] Racetams — piracetam and other compounds that are structurally related to piracetam — have few serious adverse effects and low toxicity, but there is little evidence that they enhance cognition in people having no cognitive impairments.[19]