[1][2] It can be converted into GABA by the actions of diamine oxidase (DAO) and aminobutyraldehyde dehydrogenase (ABALDH) (e.g., ALDH9A1).

[1] Putrescine is converted into 4-aminobutanal via monoamine oxidase B (MAO-B).

[3][4][5] However, biosynthesis of GABA from polyamines like putrescine is a minor metabolic pathway in the brain.

[1] The related compound γ-hydroxybutyraldehyde (GHBAL) is a prodrug of γ-hydroxybutyric acid (GHB) as well as a metabolic intermediate in the conversion of 1,4-butanediol (1,4-BD) into GHB.

[6][7] However, aliphatic aldehydes like GHBAL are caustic, strong-smelling, and foul-tasting, and ingestion is likely to be unpleasant and result in severe nausea and vomiting.