GABA (Gamma-Aminobutyric Acid) is one of the more potent depressive neuroactive peptides that is contained within brain tissue. This is because it is the primary inhibitory neurotransmitter in the mammalian central nervous system. Even though GABA taken orally is not very bioavailable, some amount may reach the brain and exert certain effects. GABA can help promote calm, relaxation, and support sleep. Double Wood's GABA 500 mg capsules are Made in the USA, Non-Gmo, Vegan Safe, and Gluten Free. Each bottle contains 300 capsules of 500mg GABA. (1,000mg per two capsules serving) Enough servings to last 150 days.