Roux-en-Y Gastric Bypass—Laparoscopic Surgery



Roux-en-Y gastric bypass is a surgery for obesity . It changes the size of the stomach and small intestine to cause weight loss by:

  • Restricting food intake—creates a small pouch to serve as the stomach, so you cannot eat as much
  • Making the body unable to absorb as many calories from the food—bypassing the first part of the small intestine, where many of the calories from food are usually absorbed

Possible Complications

Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like:

  • Bleeding
  • Infection
  • Blood clots
  • Pulmonary embolism
  • Hernia formation
  • Bowel obstruction
  • Breakdown of the staples, allowing leakage of stomach juices into the abdomen
  • Diarrhea, abdominal cramping, and vomiting
  • Dumping syndrome—occurs after eating sweets, when food moves too quickly through the small intestine causing sweating, fatigue, lightheadedness, cramping, and diarrhea
  • The need for additional surgery
  • Complications of general anesthesia
  • Death

Long-term complications include vomiting and gallstones.

Before your procedure, talk to your doctor about ways to manage factors that may increase your risk of complications such as:

  • Smoking
  • Drinking
  • Chronic disease such as diabetes



This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

a (Bariatric Surgery; Weight-Reduction Surgery)


American Society for Metabolic and Bariatric Surgery 

National Institute of Diabetes and Digestive and Kidney Diseases 


HealthLink BC 

Weight Loss Surgery 


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