Levofloxacin secretion in breast milk: A case report

Objective. To evaluate levofloxacin secretion in human breast milk. Methods. Breast milk was collected from a lactating woman during a 23-day period in which she received levofloxacin 500 mg/day and for 5 days after discontinuation of levofloxacin. The levofloxacin concentration was assayed by high-performance liquid chromatography. A two-compartment pharmacokinetic model was used to estimate peak and total levofloxacin exposure. Results. At steady state, peak levofloxacin exposure in breast milk was 8.2 μg/ml at 5 hours after dosing. Elimination pharmacokinetics followed the anticipated pattern. Conclusion. Peak levofloxacin concentration in human breast milk is similar to levels attained in plasma. However, breast-feeding mothers who take levofloxacin will expose their infants to levofloxacin in concentrations below those being studied in the pediatric population.