Psychiatric conditions including attention disorders, mood disorders, anxiety disorders, and schizophrenia pose some of the most debilitating effects on the patient population worldwide. Treatments currently used to combat such illnesses have been a significant area of research in the medical community. As more molecular mechanisms are elucidated and a deeper pathophysiologic basis is discovered for such ailments, newer pharmacologic modalities pave way to provide greater symptomatic relief and treatment with fewer side effects. Enter L-theanine, a non-essential amino acid found in green tea leaves which has been touted to have anxiolytic and cognitive enhancing properties on a wide variety of patient demographics. Furthermore, it has been recently studied for its neuroprotective qualities and antihypertensive effects. This study delves into the current understanding of common psychiatric conditions, as well as providing a summary into the current understanding of L-theanine in its potential to a wide variety of psychiatric and neurologic conditions. The apparent potential in utilizing L-theanine as a treatment modality is promising, and the limited studies available warrant continued research to provide a safe, non-toxic way in alleviating psychiatric and neurologic conditions
