Ciprofloxacin penetration into extravascular spaces in a rabbit model.

Ciprofloxacin penetration into extravascular spaces was studied in a rabbit Visking chamber model. The drug was administered (7 mg/kg) intramuscularly every 4 h for eight doses. Peak and trough drug levels by dose 8 were 1.3 and 0.35 micrograms/ml in serum and 0.61 and 0.50 micrograms/ml in extravascular sites. The ratio of extravascular site to serum free drug area under the drug curve by dose 8 was 91.1%. This potent, new antimicrobial agent appears to distribute freely to extravascular spaces in this animal model.