A nootropic agent is any substance that may alter, improve, or augment cognitive performance, mainly through the stimulation or inhibition of certain neurotransmitters. Chemically augmenting the human brain is the basis of nootropic brain enhancement-the development and experimentation with substances that can presumably improve cognition. Humans have historically sought to enhance and improve their mental and cognitive abilities. Our objective is to raise awareness among physicians in general and psychiatrists and addiction specialists in particular of the potentially dangerous phenomenon of unsupervised nootropic use among young adults who may be especially vulnerable to nootropics’ negative effects. We briefly describe the most common classes of nootropics, including their postulated or proven methods of actions, their desired effects, and their adverse side effects, and provide a brief discussion of the cases. To the best of our knowledge this has not been previously reported in the formal medical literature. We describe four cases of probable nootropic-induced psychiatric adverse effects to illustrate this theory. The misuse of nootropics-any substance that may alter, improve, or augment cognitive performance, mainly through the stimulation or inhibition of certain neurotransmitters-may potentially be dangerous and deleterious to the human brain, and certain individuals with a history of mental or substance use disorders might be particularly vulnerable to their adverse effects.