Plasma and bone concentrations of cefuroxime and flucloxacillin : oral versus parenteral administration in 20 arthroplasties

Our objective was to determine and to compare the range of bone levels of cefuroxime and flucloxacillin achieved after oral and intravenous administration in 20 arthroplasty patients, allocated to 4 groups: 1 × 500 mg or 7 × 500 mg oral cefuroxime was followed by 2000 mg Flucloxacillin i.v.; 1 × 500 mg and 7 × 500 mg oral flucloxacillin was followed by 1500 mg cefuroxime i.v. Bone samples of hip and knee were obtained. Oral administration did not result in a measurable bone concentration of any of the antibiotics. Intravenous administration resulted in measurable bone concentrations of both cefuroxime and flucloxacillin, with large inter-individual variations. The bone concentrations of intravenous cefuroxime were higher than those of flucloxacillin, despite the lower dose.Oral pretreatment had no effect on the bone concentrations after intravenous administration. No accumulation of the drugs in bone was observed.