AbstractThe amino acids γ‐aminobutyric acid, taurocholate, guanidine, glycine, and β‐alanine, known to have putative functions as neurotransmitters, when given as supplement to carbachol or decamethonium, greatly reduced the incidence of malformations produced in chicken embryos by these depolarizing cholinomimetic teratogens. In combination with the nondepolarizing teratogens neostigmine and pyridostigmine similarly beneficial effects occurred only by supplementation with γ‐aminobuty