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Mr Hisham Hammodat - General, Laparoscopic & Bariatric Surgeon

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Laparoscopic Duodenal Switch Operation

The Duodenal Switch is one of the most successful bariatric (weight loss) operations. It achieves the best long term results of excess weight loss and rates of remission of obesity related conditions, with low risk of recidivism.

The duodenal switch comprises both a restrictive and a malabsorptive component.

The Restrictive Component 
is a partial (sleeve) gastrectomy, which reduces the stomach capacity while preserving the (pylorus) valve situated at the outlet of stomach. Keeping the pylorus valve functional avoids the risk of dumping syndrome and marginal ulcers which can occur after the gastric bypass procedure where the pylorus valve is bypassed.

The Malabsorptive Component
involves rearranging of the small intestine so that a long segment of the intestine is separated from the flow of food. This segment still carries the digestive juices and is re-joined to the last portion of the small intestine where the food interacts with the digestive juices, thus limiting the amount of food (particularly fat) being absorbed.


  • Average weight loss of 70–90% of excess weight.
  • Less risk of weight regain in the long term compared to other weight loss surgeries.
  • The operation has the highest rates of remission of obesity related conditions e.g. diabetes remission rate is 99%, sleep apnoea is 99%, hypertension (high blood pressure) is 84%, and high cholesterol is 99% of patients.
  • Less food intolerance compared to other weight loss procedures. In fact people can eat a normal variety of food items albeit in much smaller portions.
  • No Dumping Syndrome. This occurs after the Gastric Bypass operation but does not occur with the Duodenal Switch operation because the pylorus valve, between the stomach and the small intestine, is preserved and remains functional.
  • Minimal risk of marginal ulcer. This can occur after the Gastric Bypass operation in 12 – 27% patients. The ulcer occurs at the section of the small intestine joined to the stomach because the intestine is put in direct contact with the stomach acid. This risk is minimal in the Duodenal Switch operation because there is no join up between intestine and stomach and also because the pylorus valve is preserved.


  • Technically a longer and more complex procedure.
  • Need of larger doses of vitamin and mineral supplements compared to other procedures.
  • Foul smelling flatulence and loose stools may be experienced especially if dietary changes have not been made to low fat choices.  

This page was last updated at 4:27PM on January 22, 2020.