Implications of Bariatric Surgery on Absorption of Nutrients and Medications

Mary Carpenter, PharmD; Mary Ellen Pisano, PharmD; Christopher M. Bland, PharmD, BCPS, FIDSA


US Pharmacist. 2016;41(12):HS-2-HS-8. 

In This Article

Abstract and Introduction


Bariatric surgeries have increased significantly in recent years as a viable long-term treatment option for severe obesity or obesity with comorbid conditions such as type 2 diabetes. These procedures, especially the Roux-en-Y gastric bypass, can have significant effects on medication and nutrient absorption. Data currently are limited on effects of bariatric surgery on specific medications. Pharmacists, as the dosage-form experts, serve an important and unique function in helping to ensure appropriate medication and nutrient therapy in the post–bariatric surgery patient in both inpatient and outpatient settings as well as during transition of care.


Obesity is a chronic medical condition associated with significant medical and psychological comorbidity, as well as increased mortality. In 2009–2010, more than one-third of adults in the United States were considered obese, defined as a body mass index (BMI) ≥30 kg/m2.[1] Evidence has shown that bariatric surgery not only serves as a means of weight reduction but also reduces morbidity and mortality rates in severely obese patients. Bariatric surgery candidates include those with a BMI ≥40, or a BMI ≥35 with one or more significant obesity-associated comorbidities, including type 2 diabetes, hypertension, obstructive sleep apnea, hyperlipidemia, obesityhypoventilation syndrome, asthma, venous stasis disease, severe urinary incontinence, severe arthritis, gastroesophageal reflux disease (GERD), nonalcoholic fatty liver disease, or nonalcoholic steatohepatitis.[2]