Also known as Arcalion or Bisbuthiamine and Enerion, Sulbutiamine is a compound of the Sulphur group and is an analogue to vitamin B1, which  is known to pass the blood-brain barrier very easily. Sulbutiamine is found to circulate faster than Thiamine from blood to brain. It is recommended for patients suffering from mental fatigue caused due to emotional and psychological stress. The best part about this compound is that it does not have most of the common side effects linked with a few nootropics.
Microdosing with Ketamine: Ketamine is a general anesthetic that is most commonly used on animals but ironically was originally devised for and tested on humans. Users of ketamine have claimed increased compassion and sensitivity to others, an increase in joy of life, and a reduced fear around death. Finding your ideal microdose of ketamine can be tricky, so it is important to start just a bit below the recommended doses. Taking ketamine sublingually (under the tongue) is the most effective and direct route of administration, and a sublingual microdose is about .75 milligrams per kilogram of body weight, although you can get a significant mood enhancement with as little as 0.2 milligrams per kilogram of body weight. I’d recommend that you never mix ketamine with any drugs that depress breathing such as alcohol, opioids, and tramadol, as it is an extremely calming agent that can produce a heavy sedative effect if you’re not careful or if you combine it with other sedative-like compounds. I’ve found a microdose of ketamine to be best combined with a trip to a float tank, or any other environment that involves sensory deprivation and introspection.
In 3, you’re considering adding a new supplement, not stopping a supplement you already use. The I don’t try Adderall case has value $0, the Adderall fails case is worth -$40 (assuming you only bought 10 pills, and this number should be increased by your analysis time and a weighted cost for potential permanent side effects), and the Adderall succeeds case is worth $X-40-4099, where $X is the discounted lifetime value of the increased productivity due to Adderall, minus any discounted long-term side effect costs. If you estimate Adderall will work with p=.5, then you should try out Adderall if you estimate that 0.5 \times (X-4179) > 0 ~> $X>4179$. (Adderall working or not isn’t binary, and so you might be more comfortable breaking down the various how effective Adderall is cases when eliciting X, by coming up with different levels it could work at, their values, and then using a weighted sum to get X. This can also give you a better target with your experiment- this needs to show a benefit of at least Y from Adderall for it to be worth the cost, and I’ve designed it so it has a reasonable chance of showing that.)
Recently I spoke on the phone with Barbara Sahakian, a clinical neuropsychologist at Cambridge University and the co-author of a 2007 article in Nature entitled "Professor's Little Helper". Sahakian, who also consults for several pharmaceutical companies, and her co-author, Sharon Morein-Zamir, reported that a number of their colleagues were using prescription drugs like Adderall and Provigil. Because the drugs are easy to buy online, they wrote, it would be difficult to stop their spread: "The drive for self-enhancement of cognition is likely to be as strong if not stronger than in the realms of 'enhancement' of beauty and sexual function." (In places like Cambridge, at least.)
We started hearing the buzz when Daytime TV Doctors, started touting these new pills that improve concentration, memory recall, focus, mental clarity and energy. And though we love the good Doctor and his purple gloves, we don’t love the droves of hucksters who prey on his loyal viewers trying to make a quick buck, often selling low-grade versions of his medical discoveries.
Barbara Sahakian, a neuroscientist at Cambridge University, doesn’t dismiss the possibility of nootropics to enhance cognitive function in healthy people. She would like to see society think about what might be considered acceptable use and where it draws the line – for example, young people whose brains are still developing. But she also points out a big problem: long-term safety studies in healthy people have never been done. Most efficacy studies have only been short-term. “Proving safety and efficacy is needed,” she says.
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]