Phenibut, also known as fenibut, phenigamma, and beta-phenyl-gamma-aminobutyric acid, is a derivative of the neurotransmitter GABA. It was developed in Russia,and there it has been used clinically since the 1960s to treat anxiety and related conditions，including insomnia(Lapin，2001). Phenibut has anxiolytic properties and is commonlycompared to benzodiazepines and baclofen.Structurally，phenibut issimilar to GABA, with the addition of the phenyl ring. This allows thecompound to more easily cross the blood-brain barrier, but also changesits activity profile (Shulgina,1986). Scientific studies demonstrate that phenibut can be safely used to treat anxiety, depression,epilepsy, speech disorders, and insomnia.
