Weight-normalized tigecycline clearances for individual subjects by age and sex group. ○, young women (18 to 50 years); •, young men (18 to 50 years); ▵, young-elderly women (65 to 75 years); ▴, young-elderly men (65 to 75 years); □, elderly women (>75 years); ▪, elderly men (>75 years).