GABA (gamma-aminobutyric acid) is an amino acid. It is the main inhibitory (calming) neurotransmitter in the brain. Neurotransmitters are chemical messengers between neurons (nerve cells). Our bodies make GABA from glutamine – a vital amino acid in the brain. Amino acids are the building blocks of proteins. GABA is a natural calming and anti-epileptic agent. It is vital for proper brain functioning. Also helps our bodies make endorphins (chemicals that make us feel happy).