Hopantenic acid (homopantothenic acid), also known as N-pantoyl-GABA, is a central nervous system depressant. Formulated as the calcium salt, it is used as a pharmaceutical drug in the Russian Federation for a variety of neurological, psychological and psychiatric conditions and sold as Pantogam (Russian: Пантогам). It is not approved for use in Europe or the United States. Hopantenic acid (homopantothenic acid), also known as N-pantoyl-GABA, is a central nervous system depressant. Formulated as the calcium salt, it is used as a pharmaceutical drug in the Russian Federation for a variety of neurological, psychological and psychiatric conditions and sold as Pantogam (Russian: Пантогам). It is not approved for use in Europe or the United States. Hopantenic acid is a homologue of pantothenic acid. While pantothenic acid is the amide of D-pantoate and β-alanine, hopantenic acid is the amide of D-pantoate and γ-aminobutyric acid (GABA). This change leads to an additional CH2 in the molecule.