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 .
Impact of Bariatric Surgery on the Pharmacokinetics Parameters of Amoxicillin
Background Bariatric surgery leads to several anatomo-physiological modifications that may affect pharmacokinetic parameters and consequently alter the therapeutic effect of drugs , such as antibiotics . The pharmacokinetics of oral amoxicillin after Roux-en-Y gastric bypass ( RYGB ) surgery is unknown . Objectives The objective of this study was to evaluate the impact of bariatric surgery on the pharmacokinetics of  amoxicillin . Methods This study was performed as a r and omized , open-label , single-dose clinical trial , with two periods of treatment , in which obese subjects ( n = 8) received an amoxicillin 500 mg capsule orally before and 2 months after the RYGB surgery . The  amoxicillin plasma concentration was determined by liquid chromatography coupled to mass spectrometry ( LC-MS/MS ) . Results After the surgery , the mean weight loss was 17.03 ± 5.51 kg , and mean body mass index ( BMI ) decreased from 46.21 ± 2.82 to 38.82 ± 3.32 kg/m2 . The mean amoxicillin area under the plasma concentration versus time curve from time zero to the time of the last quantifiable concentration ( AUC0–tlast ) increased significantly ( 3.5-fold ) ; the maximum plasma concentration ( Cmax ) increased 2.8-fold after the bariatric surgery . No correlation was found between amoxicillin absorption , BMI , and weight loss percentage . Conclusion The alterations observed in the amoxicillin pharmacokinetics suggest that obese subjects included in this trial had a substantially increase in amoxicillin systemic exposure after RYGB surgery . However , despite this increase , its exposure was lower than the values reported for non-obese volunteers . Trial Registration Identifiers :
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 .