Effect of Weight and/or Obesity on Dapsone Drug Concentrations

Inclusion Criteria: * Male and female subjects, age \>18 years, of all racial and ethnic origins. * Non-English speaking Spanish speakers will be included in the study. * We are recruiting 12 normal or underweight (BMI \<25 kg/m2), 12 overweight or obese (BMI 25-40 kg/m2), and 12 extremely obese (BMI \> 40 kg/m2) for this study. This index is calculated using the volunteer's height and weight (Formula: weight (lb) / \[height (in)\]2 x 703). Half of each group will be male; the other half will be female. Exclusion Criteria: * Pregnant or nursing or unwilling to use a reliable contraception method during the study. The effects of dapsone on pregnancy are unknown. In addition, the metabolic changes that accompany pregnancy may alter the concentration-time profile of dapsone, so that the pregnancy and post-partum state would be a confounding variable. * Abnormal liver function tests: transaminases\>10 times upper limit of normal, Alkaline phosphatase\>5 times upper limit of normal, total bilirubin\>5 times upper limit of normal. * History of allergies to dapsone, sulfones, or sulfonamides. * Dapsone, sulfones, or sulfonamides are contraindicated for any reason. * Volunteers unwilling to comply with study procedures. * Current suspected or documented infection of any kind. * Volunteers with colon resection, gastric bypass, lap band, or any other conditions inhibiting gastric absorption of drug. * Current or previous participation within 28 days of enrollment in another research study that involves the use of medication, contrast, or any other compound that may alter blood count and/or blood chemistry (liver function, kidney function or electrolyte balance), unless waved by PI. * Donation of 450 milliliters (ml) (one unit) of blood or more within 8 weeks (56 days) prior to study enrollment, unless waved by PI. * Current use of zidovudine, amprenavir, rifabutin, rifapentine, or saquinavir. * Creatinine clearance \< 70 ml/minute (min) as estimated by the Cockcroft-gault equation.