The effect of fever on antipyrine metabolism in children.

1 The elimination of antipyrine from saliva was measured in six children aged 5 months to 5 years during fever and during a control period 2-4 weeks after the cessation of fever. 2 The mean (+/- s.d.) saliva antipyrine clearance during fever, 32 +/- 13 ml kg-1 h-1, was nearly 50% less than that when the children were afebrile, 50 +/- 22 ml kg-1 h-1 (P less than 0.02). The mean saliva antipyrine half-life during fever, 15.20 +/- 5.40 h, was almost twice as long as that found when body temperature was normal, 9.18 +/- 2.49 h (P less than 0.01). The apparent volume of distribution of antipyrine was not significantly affected by fever. 3 These findings indicate that drug metabolising ability in children is impaired during fever.