gamma-Amino-beta-hydroxybutyric acid

γ-Amino-β-hydroxybutyric acid (GABOB) (brand names Gamibetal, Gabomade, Aminoxan, Bogil, Diastal, Gabimex, Gaboril, Kolpo), or β-hydroxy-γ-aminobutyric acid (β-hydroxy-GABA), is an anticonvulsant which is used for the treatment of epilepsy in Europe, Japan, and Mexico. It is also an endogenous active metabolite and analogue of the neurotransmitter γ-aminobutyric acid (GABA), and for this reason, may function as a neurotransmitter itself. Relative to GABA, GABOB has more potent inhibitory effects on the central nervous system, perhaps due to its greater capacity to cross the blood-brain-barrier. However, GABOB is of relatively low potency as an anticonvulsant when used by itself, and is more useful as an adjuvant treatment used alongside another anticonvulsant. GABOB has two stereoisomers, with the (3S) isomer d-GABOB being around twice as potent an anticonvulsant as the (3R) isomer l-GABOB.