A gastric balloon (sometimes called “intragastric balloon”) is a medical device that can help treat obesity in those who are not candidates for bariatric (weight-loss) surgery. It is a temporary method to promote weight loss and the most commonly used medical device to help patients with obesity lose weight without surgery.

Doctors perform a minimally invasive endoscopic procedure to place a gastric balloon in a patient’s stomach. Once the balloon is properly positioned, it is filled with fluid or gas, and takes up a significant amount of space in the stomach. The balloon is typically left in place for six months and then removed.

A gastric balloon decreases the amount of stomach space available to hold food, which encourages patients to consume less, leading to weight loss. It may also help to delay gastric emptying (the process during which food leaves the stomach), which enhances the feeling of fullness for longer periods. Researchers believe that a gastric balloon may also decrease the amount of ghrelin (the “hunger hormone”) the stomach produces, but more research is needed to confirm this theory.

Gastric balloon procedures are, by design, reversible; the device must be removed within six months. The balloon may be removed sooner than is recommended, but it is never a permanent solution.

Most bariatric procedures are surgeries. Two different surgical procedures—sleeve gastrectomy and gastric bypass—account for more than 97% of all bariatric procedures. The remaining 3% are gastric balloon procedures.

Gastric balloon patients typically lose approximately 23 pounds or between 6% and 15% of their total body weight during the six- to eight-month period when the device is in place. By comparison, people who lose weight by making lifestyle changes typically lose between 1% and 5% of their total body weight during the same time frame. Fluid-filled gastric balloons may lead to greater weight loss than gas-filled balloons.

A gastric balloon is a medical device that is temporarily placed in a person’s stomach, then filled with fluid or gas. The balloon occupies a portion of the stomach, which helps patients feel full and consume less food, helping them to lose weight. Patients with obesity who aren’t candidates for—or choose not to undergo—weight-loss surgery may lose more weight with a gastric balloon than they would on their own through diet and exercise.

Different types of gastric balloons are available, but they all share similarities: Each is designed to remain in the stomach for several months, taking up space so there’s less room for food and patients feel fuller than they normally would.

Some gastric balloons are placed in the stomach during an endoscopic procedure. Others are contained within swallowable, dissolvable capsules that expand into a balloon once swallowed and in the correct location.

A gastric balloon is placed into a patient’s stomach in one of two ways: via an endoscopic procedure or capsule.

• Endoscopic procedure. When a gastric balloon is placed during an endoscopic procedure, the patient receives a sedative to relax them, as well as a local anesthetic to numb sensation in the throat. The doctor places an endoscope (a long, flexible tube) into the patient’s mouth, through the esophagus, and into the stomach. The endoscope allows a camera and a deflated gastric balloon to reach the stomach. Doctors use camera guidance to place the balloon in the proper location. They then use a catheter and syringe to fill the balloon with saline. When it is filled, the balloon self-seals. One type of saline-filled gastric balloon is adjustable, so doctors can add or remove some fluid from the balloon while it is in the patient’s stomach to provide a greater feeling of fullness or reduce unwanted symptoms caused by too much pressure.

• Capsule. When a patient swallows a capsule containing a gastric balloon, it’s connected to a thin catheter that fills the balloon with gas. The location of the capsule is verified by X-ray. When doctors confirm it is in the correct location in the stomach, they inflate it with a nitrogen gas mixture; then, the balloon self-seals. Up to three balloons may be placed in a patient’s stomach over the course of three months.

After a gastric balloon is placed in the stomach, a patient needs to consume a liquid diet for one week, followed by one week of eating soft foods, before returning to a normal diet.

When it’s time to remove a gastric balloon, doctors perform an endoscopic procedure involving sedation and a local anesthetic. They puncture the balloon, drain the fluid or suck out the gas, and then remove the deflated balloon or balloons via endoscope.

A gastric balloon treats obesity without surgical intervention. Doctors may recommend a gastric balloon if a patient’s body mass index (BMI) shows that they have obesity. The BMI calculation uses a person’s height and weight to determine if their weight is in one of the following ranges: normal, underweight, overweight, or obesity. Patients with a BMI of 30 or higher have obesity.

Patients may be eligible for a gastric balloon if they have a BMI between 30 and 40, and they haven’t been able to lose weight and keep it off with other weight-loss plans.

A gastric balloon can help patients with obesity lose weight without undergoing bariatric surgery. This intervention may be a weight-loss option for patients who aren’t candidates for bariatric surgery because their BMI is not high enough.

Also, because a gastric balloon is not placed during a surgical procedure, no incisions are needed, thereby reducing the risk of infection.

Although weight regain is common among people who have had gastric balloons, a balloon may sometimes be the first successful step toward weight loss. This typically happens when the patient actively works with their primary care physician, a nutritionist, a therapist, and a gastroenterologist to adopt a lifestyle plan that includes healthy eating habits, regular physical activity, and, in many cases, medication that helps with weight loss.

Patients won’t lose as much weight with a gastric balloon as they would with bariatric surgery, but they typically lose more weight than they would if they made lifestyle changes on their own.

For patients who don’t qualify for bariatric surgery, who aren’t healthy enough to undergo it, or who prefer to avoid surgery, a gastric balloon can be an effective way to lose up to 15% of their total body weight. However, it is not recommended for patients who have previously had stomach or esophageal surgery.

The following risks are associated with a gastric balloon:

• Weight regain. A gastric balloon does not have the same long-term effect on weight loss as bariatric surgery. Many people who have gastric balloons regain weight after the device is removed. However, they generally remain at a lower weight than they were before receiving the balloon.

• Nausea, vomiting, abdominal pain. Some patients experience nausea, vomiting, or abdominal pain after they have a gastric balloon placed in their stomach. These symptoms often subside, and they can be managed with medication. If the discomfort persists, removing the gastric balloon earlier than planned should help to eliminate symptoms.

• Balloon hyperinflation or deflation. In some cases, the gastric balloon may deflate or become hyperinflated.
  
  When a gastric balloon deflates, it may leave the stomach and enter the small intestine, where it may cause a bowel obstruction. Doctors often put blue dye with saline in gastric balloons so that if a balloon leaks, the urine becomes discolored, alerting patients to seek help.
  
  In rare instances, a gastric balloon may become hyperinflated spontaneously, taking on extra fluid or air while in a patient’s stomach. This may cause nausea, vomiting, or pain. Patients usually need to have the gastric balloon removed earlier than expected.

• Pancreatitis. In rare cases, fluid-filled gastric balloons have been linked to acute pancreatitis (inflammation of the pancreas). This can occur if the balloon exerts pressure on the pancreas, leading to injury and inflammation.

• Gastric or esophageal perforation. In extremely rare cases, fluid-filled gastric balloons have been associated with gastric perforation, esophageal perforation, and even death. Esophageal or gastric perforation can occur when a gastric balloon is removed endoscopically. A gastric perforation or a gastric ulcer may occur from pressure that arises if the balloon becomes compressed against the stomach’s inner wall. Gastric and esophageal perforation are life-threatening conditions.

This article was medically reviewed by Neil Floch, MD, a Yale Medicine bariatric surgeon and director of Bariatric Surgery at Greenwich Hospital, and John Morton, MD, MPH, MHA, medical director of Bariatric Surgery for the Yale New Haven Health System.