Theanine is a unique amino acid found almost exclusively in green tea that exerts beneficial effects on brain metabolism.* Theanine induces relaxation without causing drowsiness, as measured by increased generation of alpha-waves.* Theanine may improve sensations of pleasure by affecting dopamine and serotonin neurotransmitters in the brain.* Also, theanine may exert protective effects on the brain by helping to maintain healthy metabolism of glutamate.* Jarrow Formulas® Theanine is made enzymatically from amino acids and is identical to the theanine found in green tea.