Effect of Weight and/or Obesity on Ethambutol Drug Concentrations

This study is designed to measure drug concentrations in the blood of healthy volunteers administered a single dose of ethambutol. Our hypothesis is that volunteers with a body mass index (BMI) 25-40 kg/m2 will remove ethambutol more quickly from the blood than leaner volunteers, and those with a BMI \> 40 kg/m2 will have even greater clearance than those who are leaner.