Authors measured urinary excretion of tryptophan derivatives (kynurenine way) in 13 healthy and 15 epileptic children, modifying the technique qualitatively and quantitatively. In both groups, they measure tryptophan metabolites before and after L-tryptophan overload, the dosage being 100/mg/kg of body weight. They found higher tryptophan derivative values in the group suffering a epilepsy.