γ-Amino-β-hydroxybutyric acid ( GABOB), also known as β-hydroxy-γ-aminobutyric acid ( β-hydroxy-GABA), and sold under the brand name Gamibetal among others, is an anticonvulsant which is used for the treatment of epilepsy in Europe, Japan, and Mexico.  It is a  GABA analogue, or an analogue of the neurotransmitter γ-aminobutyric acid (GABA), and has been found to be an endogenous metabolite of GABA.   
GABOB is an anticonvulsant and is used in the treatment of
GABOB is a
GABA receptor agonist. It has two  stereoisomers, and shows stereoselectivity in its actions. Specifically, (  R)-(–)-GABOB is a moderate- potency agonist of the GABA, while ( B receptor S)-(+)-GABOB is a partial agonist of the GABA B receptor and an agonist of the GABA. A receptor (  S)-(+)-GABOB is around twice as potent an anticonvulsant as ( R)-(–)-GABOB. GABOB is used medically as a  racemic mixture.
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, or β-hydroxy-GABA, is a close
structural analogue of GABA (see GABA analogue), as well as of γ-hydroxybutyric acid (GHB), phenibut (β-phenyl-GABA), baclofen (β-(4-chlorophenyl)-GABA), and  pregabalin (β-isobutyl-GABA).
Society and culture
GABOB has been referred to by the
generic name buxamine or buxamina. 
GABOB is sold primarily under the brand name Gamibetal.
It has also been marketed under a variety of other brand names including Aminoxan, Bogil, Diastal, Gabimex, Gabomade, Gaboril, Gamalate, and Kolpo.  
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