RT Journal Article SR Electronic T1 Interferon reduces hepatic drug metabolism in vivo in mice. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 459 OP 463 VO 13 IS 4 A1 G Taylor A1 B J Marafino, Jr A1 J A Moore A1 V Gurley A1 T F Blaschke YR 1985 UL http://dmd.aspetjournals.org/content/13/4/459.abstract AB The effects of two highly purified human leukocyte interferons (IFN-A and IFN-AD) on drug-metabolizing capacity in mice have been investigated. IFN-AD was found to produce significant changes in antipyrine half-life, assessed by analysis of 14CO2 exhalation rates following 14C-antipyrine administration. By contrast, IFN-A, which has considerably less antiviral potency than IFN-AD, was found to have no effect on antipyrine half-life. The administration regimen was found to markedly alter the effects seen with IFN-AD. When IFN-AD was given as single daily doses (5 X 10(7) units/kg/day X 3 days), the half-life of antipyrine increased by a mean of 40% (from 21.0 to 28.9 min). However, when a smaller daily dose (3 X 10(7) units/kg/day) was given as a continuous infusion, the antipyrine half-life increased by more than 3-fold (from 20.8 to 68.5 min) after 3 days of administration. Continued infusion for a further 3 days produced no additional change in antipyrine half-life. These results demonstrate that human leukocyte interferons can significantly inhibit hepatic metabolic activity in vivo.