Lymecycline or doxycycline for treatment of urinary-tract infections: a comparison of attained urine concentrations.

The urine and serum concentrations of lymecycline and doxycycline were investigated in a cross-over study in ten volunteers. Both drugs were found in therapeutic serum levels but lymecycline had a mean urine concentration of 240 microgram per ml compared to 60 microgram per ml of doxycycline. The results are discussed with regard to treatment of some urinary-tract infections.