Multiple-Dose Pharmacokinetics And Safety Of Amoxicillin/Clavulanate In Healthy Elderly Subjects

Background: Amoxicillin/clavulanate is a widely used oral formulation of penicillin combined with a beta-lactamase inhibitor. When using amoxicillin/clavulanate in the elderly, the risk of adverse drug reaction may be greater. This study alined to evaluate the pharmacokinetics (PKs) and safety of multiple-dose amoxicillin/ clavulanate administration in healthy elderly subjects and to compare the observed PK profiles with those in healthy younger adults. An open-label, one-sequence, multiple administration study was conducted in 16 healthy elderly subjects. Materials and methods: Subjects orally received amoxicillin and clavulanate 750/187.5 twice daily for 9 days. For PK analysis, serial blood samples were collected up to 12 hours after the last administration of amoxicillin/clavulanatc. The demographic and PK data of this study were compared to those of healthy young adults from a separate study with a similar design. Safety assessments including clinical laboratory tests, physical examination, vital signs, and adverse event (AE) monitoring were performed throughout the study. Results: All AEs were mild, and no serious AEs were reported in this study. The systemic exposure of amoxicillin and clavulanate was similar to 90% and 60% higher, respectively. in the elderly subjects than in the younger subjects. However, the time required to reach maximum concentration at steady state and the elimination half-life were similar in the two age groups. Conclusion: Although multiple administration of amoxicillin/clavulanate 750/187.5 mg was safe and well-tolerated, the systemic exposure of amoxicillin and clavulanate was higher in elderly subjects than in younger subjects.