Impact of Bariatric Surgery on the Pharmacokinetics Parameters of Amoxicillin

• Published in: Obesity surgery Vol. 29; no. 3; pp. 917 - 927
• Main Authors: Rocha, Marina Becker Sales, De Nucci, Gilberto, Lemos, Francisco Ney, de Albuquerque Lima Babadopulos, Rodrigo Feitosa, Rohleder, Andrea Vieira Pontes, Fechine, Francisco Vagnaldo, Antunes, Natalícia J., Mendes, Gustavo D., do Nascimento, Demetrius Fernandes, de Moraes, Manoel Odorico, de Moraes, Maria Elisabete Amaral
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.03.2019; Springer Nature B.V
• Subjects: Administration, Oral; Adult; Amoxicillin - administration & dosage; Amoxicillin - blood; Amoxicillin - pharmacokinetics; Anti-Bacterial Agents - administration & dosage; Anti-Bacterial Agents - blood; Anti-Bacterial Agents - pharmacokinetics; Antibiotics; Body Mass Index; Chromatography, Liquid; Female; Gastric Bypass; Gastrointestinal surgery; Humans; Male; Medicine; Medicine & Public Health; Middle Aged; Obesity, Morbid - blood; Obesity, Morbid - metabolism; Obesity, Morbid - surgery; Original Contributions; Penicillin; Pharmacokinetics; Surgery; Tandem Mass Spectrometry; Weight Loss - physiology; Obesity; Pharmacokinetics; Amoxicillin; Bariatric surgery; Gastric bypass
• ISSN: 0960-8923; 1708-0428
• DOI: 10.1007/s11695-018-3591-3

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 randomized, 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/m 2 . The mean amoxicillin area under the plasma concentration versus time curve from time zero to the time of the last quantifiable concentration (AUC 0–tlast ) increased significantly (3.5-fold); the maximum plasma concentration ( C max ) 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: NCT03588273