title: Pharmacokinetics of moxifloxacin in plasma and tissue of morbidly obese patients.
abstract: OBJECTIVE
  To assess the pharmacokinetics of moxifloxacin in morbidly obese patients.
  
  
  METHODS
  Twelve morbidly obese patients (2 male/10 female, age 25-61 years, weight 98-166 kg, body mass index 43.0-58.2 kg/m(2)) scheduled for gastric bypass surgery were treated with 400 mg of moxifloxacin orally once daily for 3 days and with 400 mg of moxifloxacin intravenously on day 4 (day of surgery). Pharmacokinetic analysis was performed on day 1 and day 4. Specimens of small intestine, greater omentum and subcutaneous adipose tissue were collected intraoperatively 1.8-3.7 h after moxifloxacin infusion. Moxifloxacin concentrations were determined by HPLC.
  
  
  RESULTS
  The plasma pharmacokinetics (mean ± SD) was comparable to historical data in normal-weight subjects. Oral bioavailability was 79.6% ± 11.5%. After intravenous administration, plasma clearance was 9.6 ± 2.0 L/h, volume of distribution was 165 ± 30 L and area under the curve was 43.7 ± 11.8 mg·h/L. Linear regression analysis showed the volume of distribution to be better correlated with ideal body weight, lean body weight, fat-free mass or height (R(2) = 0.60-0.67, P = 0.001-0.003) than with total body weight (R(2) = 0.46, P = 0.015). Whereas mean tissue concentrations in small intestine (6.99 ± 2.34 mg/kg) were twice the concomitant plasma concentrations, the concentrations in greater omentum (0.801 ± 0.168 mg/kg) or subcutaneous fat (0.638 ± 0.180 mg/kg) were only one-quarter of those.
  
  
  CONCLUSIONS
  The pharmacokinetics of moxifloxacin is not significantly affected by morbid obesity. No dose adjustment seems to be necessary in this particular population.
authors: Department of Anesthesiology and Intensive Care, Charité University Hospital Berlin-Campus Benjamin Franklin, Hindenburgdamm 30, D-12203 Berlin, Germany. martin.kees@charite.de
authors: Martin G
authors: MG
authors: Kees
authors: Susanne
authors: S
authors: Weber
authors: Frieder
authors: F
authors: Kees
authors: Thomas
authors: T
authors: Horbach
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D001372:Aza Compounds / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D001682:Biological Availability; D001823:Body Composition; D015992:Body Mass Index; D005260:Female; D024841:Fluoroquinolones; D015390:Gastric Bypass; D006801:Humans; D007421:Intestine, Small / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D000077266:Moxifloxacin; D009767:Obesity, Morbid / Q000097:blood / Q000378:metabolism*; D009852:Omentum / Q000378:metabolism; D011804:Quinolines / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D000890:Anti-Infective Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D011804:Quinolines; D000077266:Moxifloxacin