Table 6

Radiometabolite patterns in the excreta and bile of bile duct-cannulated dogs following oral and intravenous administration of [14C]gemifloxacin mesylate

CompoundPercentage of Administered Dose
Oral (24 mg fb/kg)Intravenous (10 mg fb/kg)
UrineBileFecesTotalUrineBileFecesTotal
Gemifloxacin6.62.741.350.619.09.416.444.8
Gemifloxacin acyl glucuronide0.41.7N.D.2.10.65.7N.D.6.3
E-Isomer of gemifloxacin1.00.32.94.22.50.72.45.6
Carboxylic acid derivative0.30.5N.D.0.8N.S.2.0N.D.2.0
Hydroxymethyl gemifloxacinN.D.0.2N.D.0.2N.D.1.1N.D.1.1
O-Desmethyl gemifloxacin0.3N.S.N.D.0.30.51.7N.D.2.2

Radiometabolite patterns were determined in pooled 0- to 24-h urine and bile samples and in extracts of 0- to 48-h fecal extracts. Data are mean values (n = 3).

  • N.D., not detected; N.S., the carboxylic acid derivative of gemifloxacin in the urine after intravenous administration andO-desmethyl gemifloxacin in bile after oral administration did not separate adequately from other minor component(s) under the analytical conditions used. However, the co-eluting peaks together accounted for <1% of the dose in each matrix. Traces of gemifloxacin glutamate were also detected in the urine and bile after both routes of administration but were below the limit of quantification (<0.05% of dose).