15 most common smart drugs By Lila MacLellanSeptember 20, 2017
The one that got my attention was non addictive, & is/was OTC. "Modafinil", & other "Nootropics".

[qz.com]

Not all drug users are searching for a chemical escape hatch. A newer and increasingly normalized drug culture is all about heightening one’s current relationship to reality—whether at work or school—by boosting the brain’s ability to think under stress, stay alert and productive for long hours, and keep track of large amounts of information. In the name of becoming sharper traders, medical interns, or coders, people are taking pills typically prescribed for conditions including ADHD, narcolepsy, and Alzheimer’s. Others down “stacks” of special “nootropic” supplements.

For obvious reasons, it’s difficult for researchers to know just how common the “smart drug” or “neuro-enhancing” lifestyle is. However, a few recent studies suggest cognition hacking is appealing to a growing number of people. A survey conducted in 2016 found that 15% of University of Oxford students were popping pills to stay competitive, a rate that mirrored findings from other national surveys of UK university students. In the US, a 2014 study found that 18% of sophomores, juniors, and seniors at Ivy League colleges had knowingly used a stimulant at least once during their academic career, and among those who had ever used uppers, 24% said they had popped a little helper on eight or more occasions. Anecdotal evidence suggests that pharmacological enhancement is also on the rise within the workplace, where modafinil, which treats sleep disorders, has become particularly popular.
Mathery

In Silicon Valley, where the Nootropic market is most developed, devotees typically take a cocktail of pills, often mixing natural supplements that are readily available and legal, with lab-designed drugs that may be unregulated in the US, but still easily purchased online and shipped in from other countries.

But do these brain-hacking drugs actually make you smarter? The answers are murky at best.

Here’s a cheat sheet of 15 of the most commonly touted cognitive-boosting pills that have also been studied in clinical trials.