Avanços em Farmacoepidemiologia e Segurança de Medicamentos

Abstrato

Pharmacokinetic Changes Secondary to Roux en Y Gastric Bypass

Christopher Giuliano, Sheila M. Wilhelm and Pramodini B. Kale-Pradhan

Objective: To review the influence of Roux-en-Y gastric bypass (RYGB) on pharmacokinetic parameters of medications.
Data sources: PubMed was searched from inception to September 2012 to identify studies. Search terms included bariatric surgery, gastric bypass, Roux-en-Y, pharmacokinetic, and absorption. Studies included for this review were limited to English language studies published in full.
Data synthesis: Obesity is a major health care concern and is on the rise. This has led to an increasing number of bariatric surgeries. Such procedures may have profound effects on pharmacokinetic parameters of many medications depending on the extent of surgical changes that are made. Surgical procedures such as RYGB are most likely to affect medication absorption. Factors that may affect medication absorption in RYGB patients include changes in intestinal or gastric pH, surface area, intestinal metabolism and transport mechanisms. Published studies have been primarily conducted in RYGB patients and have shown varied effect on overall absorption of medications.
Conclusions: RYGB may have profound effects on medication absorption. Predicting absorption is difficult due to interplay of several factors including, changes in intestinal surface area, intestinal metabolism, efflux pumps, active transporters and gastrointestinal pH. Future studies are needed, particularly studies evaluating medications that have a low bioavailability and are commonly used in the bariatric surgery population.