“Nootropic” essentially means something that enhances your cognition, says Philip Muskin, MD, professor of psychiatry at Columbia University Medical Center’s Department of Psychiatry. “There are a bunch of things that fall into that class,” he says. For example, stimulant drugs like Adderall and Dexedrine are nootropics. And even things like caffeine, nicotine, and L-theanine could be considered nootropics, because they have a stimulant effect, he says. “Though, honestly there’s nothing that is truly like, Wow, this will make you a genius,” he says.