Patients given oral beta-lactams and macrolides warrant close monitoring due to unpredictable absorption post-bariatric surgery , whereas oral fluoroquinolones and linezolid may not be affected .
Several studies also showed decreased absorption following RYGB , as well as lower serum exposure in patients with obesity compared to non-obese controls .
The purpose of this study was to conduct a systematic review of the existing literature to determine the effect of bariatric surgery on various pharmacokinetic parameters of oral antibiotic absorption as well as overall patient outcomes .
Oral bioavailability of moxifloxacin after Roux-en-Y gastric bypass surgery.
OBJECTIVES Roux-en-Y gastric bypass surgery is the most commonly performed procedure for the treatment of morbid obesity . This anatomical alteration may affect the absorption and consequently the bioavailability of oral drugs . This study aims to investigate the oral bioavailability of moxifloxacin in 12 healthy volunteers who underwent gastric bypass surgery .  PATIENTS AND METHODS In this r and omized crossover study , each subject received two single st and ard doses of 400 mg of moxifloxacin orally or intravenously administered on two occasions separated by a washout period of 1 week . Serial venous blood sample s were drawn up to 72 h after dosing and  moxifloxacin plasma levels were measured by a vali date d HPLC method with fluorescence detection . [ clinical trials.gov data base ( identifier : NCT01130922 ) . ] RESULTS After oral dosing , moxifloxacin plasma concentrations reached a maximum ( C(max ) ) of 3.38 ± 1.41 mg/L after 1.75 h ( 0.75 - 4.00 ) . After intravenous dosing , C(max ) and T(max ) were 4.53 ± 1.43 mg/L and 1.03 h ( 0.75 - 2.50 ) , respectively . The mean areas under the plasma concentration time curve extrapolated to infinity ( AUC(∞ ) ) were 46.2 ± 1.4 mg · h/L after oral dosing and 52.3 ± 1.3 mg · h/L after intravenous dosing , result ing in a mean oral bioavailability of 88.32 % [ 90 % confidence interval ( CI ) 85.64%-91.08 % ] . CONCLUSIONS This study confirms that exposure to moxifloxacin is equivalent for oral and intravenous administration of 400 mg dosages in healthy volunteers who underwent gastric bypass surgery . But these exposures were more than 50 % higher than those described for subjects without gastric bypass . This may suggest a higher enterohepatic recirculation of moxifloxacin after gastric bypass
Patients given oral beta-lactams and macrolides warrant close monitoring due to unpredictable absorption post-bariatric surgery , whereas oral fluoroquinolones and linezolid may not be affected .
Several studies also showed decreased absorption following RYGB , as well as lower serum exposure in patients with obesity compared to non-obese controls .
The purpose of this study was to conduct a systematic review of the existing literature to determine the effect of bariatric surgery on various pharmacokinetic parameters of oral antibiotic absorption as well as overall patient outcomes .