Antipyrine salivary clearance and half-life and the rate of formation of three principal metabolites of antipyrine (4-hydroxyantipyrine, 3-hydroxymethylantipyrine and norantipyrine) were assessed in nine children with congenital adrenal hyperplasia, six of whom were salt-losers and three of whom were non-salt-losers. No differences were found in comparison with data obtained in normal children.