Sulbutiamine is a synthetic derivative of thiamine or vitamin B1, one of the most important medication needed in a basic health system. Unlike thiamine, sulbutiamine crosses the blood-brain barrier with elegant efficacy, property that makes the substance especially attractive for the ones looking for fast acting, short-term nootropic benefits with few reported side effects.
Thus, sulbutiamine is used for chronic fatigue, memory, psycho-behavioral inhibition, and even erectile dysfunction. Although the exact mechanism of action is rather unknown, it is thought to occur through the upregulation of the reticular activating system, which is the center of arousal and motivation in the brain. This may help explaining the anecdotes we get from users, who find subultamine to “wakes you up from a long day and makes you ready again“, by probably potentiating cholinergic activity in the brain.
Sulbutiamine has also been reported to be “psychologically pleasant” by its users. Indeed, In a study of patients suffering from major depressive disorder and accompanying psycho-behavioral inhibition, those treated with Sulbutiamine for four weeks (600 mg per day) were significantly less incapacitated than the placebo group in all of the various facets (affective, cognitive, emotional, behavioral) and a considerable decrease in shyness was observed.
Besides that study, there is actually not much more to say about this compound. Sulbutiamine might be of particular interest for people who are dealing with shyness, yet its nootropic potential is still highly uncertain and controversial, and no long-term studies have taken place yet. Hence we do not really have good reasons to strongly recommend. However, to be fair, at lower doses, sulbutiamine has few reported side effects, making the supplement safe in the short-term eventual use. You can give it a try.