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
Roux-en-Y Gastric Bypass
Roux en Y
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Possible Complications

If you are planning to have Roux-en-Y gastric bypass, your doctor will review a list of possible complications, which may include:

  • 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—This 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 diseases, 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 

Weight Control Information Network 


HealthLink BC 

Weight Loss Surgery 


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