PHARMACOKINETICS OF INDOMETHACIN IN THE ELDERLY

In a cross-sectional study the pharmacokinetics of indomethacin were s tudied in old and young adults without manifest organ failure. Total c learance of indomethacin after a single oral dose of 50mg was 0.8 ml/m in/kg in elderly individuals (mean 79.5 +/- 1.3 years) compared with 1 .4 ml/min/kg in younger individuals (mean 36.9 +/- 3.0 years). The app arent elimination rate constant averaged 0.23 h-1 in the aged and 0.32 h-1 in the young people. Oral bioavailability was close to 1 in the y oung but 0.77 in the elderly. The apparent volume of distribution was similar in each group. Based on these results it is suggested that the maintenance dose of indomethacin be reduced by 25% in the elderly.