Pharmacokinetics of a sustained-release product of indomethacin in the elderly.
The pharmacokinetics of indomethacin (Indo) was studied in 10 healthy elderly male volunteers (age 67-81 years) following the oral administration of a single 75-mg dose of a sustained release form of Indo. The total and free plasma and erythrocyte concentrations of Indo were determined by a specific high-pressure liquid chromatographic method. A maximum concentration (Cmax) of 4.28 +/- (SE) 0.43 micrograms/ml was reached after 1.85 +/- 0.22 h. The area under the plasma concentration versus time curve (AUC) was 22.83 +/- 2.70 micrograms ml-1 h and the plasma elimination half-life was 4.34 +/- 0.64 h. The maximum concentration of Indo in the red blood cells was 0.123 +/- 0.013 microgram/ml and was obtained at 1.95 +/- 0.14 h after drug administration. The erythrocyte concentrations of Indo represented 2.4% of the total plasma levels of Indo whereas only 1.3% of the drug was unbound to plasma proteins. The Cmax and AUC values determined in the elderly were approximately double the values reported in young adults for the same dose.
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D003692:Delayed-Action Preparations; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D007213:Indomethacin / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D011485:Protein Binding
D003692:Delayed-Action Preparations; D007213:Indomethacin