Phenibut (ß-Phenyl-γ-Aminobutyric Acid): an Easily Obtainable "Dietary Supplement" With Propensities for Physical Dependence and Addiction.

PURPOSE OF REVIEW: Phenibut (ß-phenyl-γ-aminobutyric acid) is a psychoactive GABA analogue currently being marketed online as an anxiolytic and nootropic dietary supplement. Its use is growing in popularity, but its pharmacological activity is well beyond that of a conventional nutritional supplement, and similar to that of a prescription strength sedative. This review will focus on the potential adversities of phenibut use and will discuss what treatment options may be beneficial to afflicted patients. RECENT FINDINGS: Over the last several years, multiple case reports have highlighted phenibut's potential to produce the conditions of physical dependence, withdrawal, and addiction. In cases involving intoxication, patients have presented with a varying degree of mental status changes, from being minimally responsive to manifesting symptoms of an agitated delirium. Phenibut is a potent psychoactive substance with GABAB agonist properties, which is emerging as a drug of misuse through growing internet sales. Its marketing as a "dietary supplement" is inaccurate and misleading, given its pharmacological profile and ability to induce the physiological changes associated with withdrawal and physical dependence.