The Biliopancreatic Diversion – Duodenal Switch (BPD-DS)

BPD_DS imageThe biliopancreatic diversion with duodenal switch goes by many names. Some refer to it by the initials BPD-DS. Many call it the “duodenal switch” or just “the switch” for short. The National Institutes of Health refers to the procedure as an “extensive gastric bypass with duodenal switch.” While less commonly performed than the gastric bypass, this operation has received a great deal of attention recently, particularly on the internet, because it provides excellent weight loss while allowing you to eat larger portions than a gastric bypass.

In the BPD/DS, roughly one half of the stomach is permanently removed. The stomach goes from the shape of a small pineapple to the size and shape of a banana. The pylorus, which is the valve at the outlet of the stomach, remains intact. The stomach is then connected to the last 250 centimeters (8 feet) of small intestine. The remainder of the small intestine is connected 100 centimeters from the end of the small bowel, forming the common channel, where food mixes with the digestive enzymes.

The BPD-DS is a substantially “bigger” operation than the gastric bypass. It is a bigger operation for 2 reasons. First, it is the only bariatric operation where a major portion of the stomach is permanently removed — this makes the procedure completely irreversible. Second, a large section of small intestine is bypassed, resulting in substantial malabsorption. This means that the risks of long-term nutritional deficits are greater.

Why would someone want to have a larger operation?

The BPD-DS has 2 major advantages:

  • The pylorus remains intact: this usually keeps dumping syndrome from occurring after surgery (although you may have different dietary restrictions)
  • Since the stomach pouch is larger than with other bariatric operations, you can eat larger portions than with the gastric bypass or LAP-BAND®.

Living with the BPD-DS

It is necessary to take a number of nutritional supplements after the operation than after gastric bypass. These include:

  • Multivitamins (usually twice per day)
  • Iron supplements (usually twice per day)
  • Calcium (usually twice per day)
  • ADEKs (fat-soluble vitamins) usually 3 times per day


Additionally, there are some very significant side effects that accompany this procedure, including:

  • Frequent soft bowel movements (up to 4-6 per day)
  • Frequent passing of foul-smelling gas
  • Change in body odor
  • Gas pains and bloating
  • Hair loss
  • Intolerance of certain foods (varies from person to person)

Deciding on the BPD-DS

The decision about which operation is best for you is a complicated one. Although the information presented here may be helpful, you will be able to learn substantially more about the benefits and risks of the BPD-DS operation during you consultation with the bariatric team at Mount Sinai. To arrange an appointment, click here.