Influence of age on the enantiomeric disposition of ibuprofen in healthy volunteers

• Published in: British journal of clinical pharmacology 2003-06, Vol.55 (6), p.579-587
• Main Authors: Tan, Soo Choon, Patel, Bhavesh K., Jackson, Stephen H. D., Swift, Cameron G., Hutt, Andrew J.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Aging - metabolism; Anti-Inflammatory Agents, Non-Steroidal - chemistry; Anti-Inflammatory Agents, Non-Steroidal - metabolism; Anti-Inflammatory Agents, Non-Steroidal - pharmacokinetics; Biological and medical sciences; Bones, joints and connective tissue. Antiinflammatory agents; Drug Disposition; elderly; Humans; ibuprofen; Ibuprofen - chemistry; Ibuprofen - metabolism; Ibuprofen - pharmacokinetics; Medical sciences; pharmacokinetics; Pharmacology. Drug treatments; Stereoisomerism; stereoselectivity
• ISSN: 0306-5251; 1365-2125
• DOI: 10.1046/j.1365-2125.2003.01806.x

Aims To determine the influence of age on the enantioselective disposition of ibuprofen in humans. Methods Healthy young (n = 16; aged 20–36 years) and elderly (n = 16; aged 66–84 years) volunteers were given a 400‐mg oral dose of racemic ibuprofen, and blood and urine samples were collected for 24 h post drug administration. Serum concentrations, total and free, and urinary excretion of both enantiomers of ibuprofen together with the urinary excretion of the stereoisomers of the two major metabolites of the drug, both free and conjugated, were determined by high‐performance liquid chromatography. Results Ageing had little effect on the distribution and metabolism of R‐ibuprofen, unbound clearance of the R‐enantiomer via inversion being approximately two‐fold that via noninversion mechanisms in both age groups. In contrast, the free fraction of S‐ibuprofen was significantly greater [33%; young 0.48 ± 0.10%; elderly 0.64 ± 0.20%] mean difference −0.16; 95% confidence interval (CI) −0.05, −0.27; P