A comparative study of the distribution of ofloxacin and ciprofloxacin in prostatic tissues after simultaneous oral ingestion

ABSTRACT

 To determine the levels of two quinolones, ofloxacin and ciprofloxacin, potent broad-spectrum antibiotics with very good oral bioavailability and low minimum inhibitory concentrations (MICs) for most pathogens, in the prostates of patients who underwent transurethral resection of the prostate (TURP) after oral ingestion for surgical prophylaxis.

Patients and methods

 Twenty-eight patients with BPH requiring a TURP ingested 250  mg of both drugs 2–4  h before operation. The levels of the drugs in the serum and prostate were measured using high-performance liquid chromatography and the levels of both drugs determined at the 6 and 9 o'clock positions in the prostate to examine any local variations in drug concentration.

Results

 Ofloxacin concentrations were significantly higher in the serum and prostatic tissues compared with ciprofloxacin for the same dose, but its penetrance into the prostate was lower. This mainly reflected its higher oral bioavailability. Both drugs were present in concentrations 50% higher at the 6 o'clock than at the 9 o'clock position but both exceeded the MICs for most Gram-negative organisms except Pseudomonas.

Conclusion

 Ofloxacin has the advantage against ciprofloxacin of exceeding the MICs for Staphylococcus and Chlamydia. However, ciprofloxacin has the advantage of having prostate-to-serum ratios of unity, but for the same dose the prostatic concentrations of ofloxacin is significantly higher.