Antipyrine absorption and disposition in the elderly.

Area of Science:

• Pharmacokinetics and Drug Metabolism
• Gerontology and Aging Research

Background:

• Age-related changes in drug metabolism and elimination can impact therapeutic efficacy and safety.
• Understanding how aging affects drug absorption and clearance is crucial for optimizing pharmacotherapy in older adults.

Purpose of the Study:

• To investigate the effects of age and gender on the pharmacokinetics of antipyrine.
• To assess age-related differences in antipyrine absorption following oral administration in fasting and fed states.

Main Methods:

• A single 1.0-gram dose of antipyrine was administered intravenously and orally (fasting and postprandial) to young (24-41 years) and elderly (62-77 years) volunteers.
• Plasma antipyrine concentrations were measured over 24 hours post-dose.
• Key pharmacokinetic parameters including elimination half-life, clearance, peak plasma concentration (Cmax), and time to peak concentration (Tmax) were determined.

Main Results:

• Elderly men exhibited a significantly prolonged elimination half-life (17 vs. 11 h) and reduced clearance (32 vs. 54 ml/min) compared to young men.
• No significant age-related differences in half-life or clearance were observed between elderly and young women.
• Oral administration of antipyrine, both fasting and postprandial, did not reveal significant age-related differences in Cmax, Tmax, or absolute bioavailability.

Conclusions:

• Aging may lead to reduced antipyrine clearance in men, suggesting potential age-related alterations in hepatic drug metabolism.
• There is no evidence of impaired gastrointestinal absorption rate or extent of antipyrine in the elderly.
• Gender-specific differences in age-related pharmacokinetic changes warrant further investigation.