Metabolism of Ketoprofen Following Single Rectal Dosage in Elderly Subjects

Abstract

Ketoprofen, a non-steroidal anti-inflammatory drug, was given to 7 elderly subjects at a single rectal dose of 75mg. Any abnormalities were not seen in clinical and physical findings.
Serum GOT and GPT were slightly elevated in one subject, and serum urea was a little increased in two subjects. Besides these, no abnormalities of clinical and physical findings were indicated.
We found that ketoprofen had a wide safety region even in elderly subjects. The maximum concentration of ketoprofen in plasma was reached at 0.5-2.0 hr.
The urinary excretion of total ketoprofen (unchanged plus conjugated) during 72 hr after administration was 35.82±6.25% of dose, and approximately 97% of the urinary total ketoprofen in the form of glucuronide. Cumulative urinary excretion (% dose) of the elderly subjects was lower than that of adults, and its clearance of the elderly was also lower.
The half-life in the plasma of the elderly subjects was 1.54±0.35 hr, which was not different from the half-life of healthy adult subjects. This result shows that elderly subjects are capable of metabolizing ketoprofen as effectively as healthy adult subjects.