Bariatric Surgery FAQ

Gastric Bypass Complications

Gastric Bypass Complications - Bariatric Fusion

Gastric bypass surgery has helped many people overcome obesity and weight management issues, but any kind of surgery can still present with a complication risk.

Gastric bypass complications vary in degree of severity, from being fairly manageable to causing extreme pain and other complications.

Luckily, there are many ways to mitigate most of these risks and there are also ways to treat some of the symptoms that may arise post-surgery.

This article will explain some of the most common complications that arise from gastric bypass surgery and include some helpful advice on how to avoid and treat them.

complications of gastric bypass

Gastric Bypass Complication

Anastomotic Leakage

Anastomotic leakage is one of the more severe side effects of gastric bypass surgery and occurs when contents leak from the internal surgical connection site.

Most leaks develop about 3 days after surgery and can be identified by symptoms of abdominal pain and fever.

It has also been found that some patients experience pain in their left shoulder when they have a leak.

The anastomotic leak can cause peritonitis. This is inflammation of the tissue that lines the abdominal wall. It can lead to rapid heart rate, abdominal pain, and fatigue after gastric sleeve and gastric bypass surgery.

In other scenarios, the leakage may result in a fistula or an abscess, which is are some of the most notable Roux-En-Y gastric bypass side effects.

Dumping Syndrome

Dumping Syndrome results when the stomach empties into the small intestine faster than normal without full digestion occurring.

This can take the form of Early Dumping (occurring about 20 minutes after eating) or Late Dumping (occurring up to 3 hours after eating), both of which are associated with different symptoms.

Early dumping is characterized by symptoms of bloating, abdominal cramps, dizziness, and nausea after gastric sleeve surgery. Late Dumping is associated with confusion, shaking, irregular heartbeat, and fainting.

The good news is dumping syndrome can often be treated with simple changes to the diet like increasing protein and fiber intake, limiting high sugar and high fat, and eating 5-6 small meals per day.

Excess Skin

This is a direct side effect of the rapid weight loss that occurs following bariatric surgery. Skin stretches to accommodate body mass and losing weight results in excess skin that does not have enough elasticity to shrink back.

Some people are not bothered by this and others are extremely self-conscious about the loose and sagging skin.

Even if this doesn’t bother you, it should be noted that it can lead to rashes, chafing, and infection over time.

If you are wondering how to tighten loose skin after gastric bypass without plastic surgery, you can do so by eating a healthy diet, looking into collagen supplements, exercise, and skin care routines.

In more severe cases, you can opt to have excess skin surgically removed with post-bariatric plastic surgery.

Internal Hernia

A symptom that affects some patients after bariatric surgery are internal hernias. This is defined as the protrusion of the intestine through the abdominal tissue wall.

They generally occur in patients who undergo Roux-En-Y gastric bypass. An internal hernia can present within a few weeks of surgery or up to 3 years after surgery. Symptoms include pain while bending, lifting, or coughing. Individuals can also see nausea and vomiting as symptoms.

Hernias can be treated with diagnostic laparoscopy. Many people are predisposed to hernias due to the position of their Roux limb or a mesenteric defect.

For this reason, doctors act with care and often decide on a patient-specific surgical approach for weight loss surgery.

Stomal Stenosis

Also called anastomotic stenosis, this condition refers to a narrowing of a new junction between the small intestine and the stomach pouch.

The stricture can occur about 3-4 weeks after gastric bypass surgery. Those who smoke, take aspirin, or take other anti-inflammatory meds increase their risk of stenosis even years after surgery.

The symptoms include nausea, difficulty swallowing and eating, feeling full in the middle part of the abdomen (lasting long after eating), and vomiting after gastric sleeve surgery.

This condition is treated with a procedure known as endoscopic dilation. In the rare case that endoscopic dilation fails, surgical treatment may be taken.


Pain after gastric bypass surgery can be caused by a number of factors. Typically, the common causes are the incision site and CO2 build up.

Gastric bypass surgery involves an incision that is made under the ribs to attach the intestines that have been re-routed.

This results in bruised muscles and nerve damage that can cause horrible pain on the left side after gastric bypass surgery. The pain can luckily be treated by minor improvements in posture.

Another type of pain results from residual CO2 that is left in the abdominal cavity after it has been used to inflate the abdomen during surgery.

The CO2 collects at the left upper side of the abdomen and the left shoulder. This can be prevented by starting to move as soon as possible after surgery, ensuring that your healthcare provider allows you to move. It can also be prevented by practicing deep breathing.


Dehydration following gastric bypass surgery is usually the result of a decreased stomach volume, which hinders patients from consuming as much water as they used to and watery bowel movements because of improper digestion.

Symptoms of thirst, dry skin, dry mouth, dark urine, and light-headedness are often observed in patients with dehydration.

The best prevention method here is making sure that you drink enough water before and after surgery. Patients are encouraged to take small sips as they adjust to the decreased volume of the stomach.

The symptoms may often be temporary, but if they persist, you should consult your doctor immediately post-bariatric surgery.


Malnutrition after gastric bypass is one of the side effects that may manifest long after gastric bypass surgery and well into your recovery period.

The side effects of malnutrition present themselves, even years later, as anemia, bone disorders, neurological disorders, and decreased muscle health.

This can occur due to new difficulties with eating or digesting certain foods. However, malnutrition typically presents in patients who do not take their prescribed bariatric multivitamins.

For example, one out of two patients experience iron deficiency anemia 5 years after surgery, which is why iron-rich multivitamins, such as the bariatric chewable multivitamin with iron, are initially prescribed to patients.

Further down the line, patients might be cleared by their healthcare provider to take bariatric capsule multivitamins with iron.

Malnutrition can be avoided when maintaining prescribed multivitamins for life post-surgery.


This is a very common symptom that manifests after surgery, yet its direct cause remains unknown.

Many people believe that infrequent bouts of hiccups after gastric sleeve and gastric bypass surgery can be ascribed to poor portion control and eating too quickly.

The hiccups generally subside after a few days or weeks, but it is recommended that you consult your doctor if the hiccups persist.

Patients are often encouraged to practice mindful eating, eating slowly and consciously being aware of each bite in order to avoid hiccups.

Hormonal Changes

As patients begin to recover from gastric bypass surgery, they may start to notice changes in the body. One of the most noticeable changes includes hormone changes after bariatric surgery.

Post-surgery patients experience changes in the hormones estradiol, testosterone, and free testosterone. In perimenopausal women, changes in estrogen and leptin has been found.

Some of these hormonal changes can increase fertility after bariatric surgery.

Hormones related to hunger and satiety may also be affected. Research on the effects of these hormonal changes has been sparse and it is unclear to what degree they may affect certain patients after surgery.

For the most part, it can positively reduce or eliminate the presence of high blood pressure and Type 2 diabetes. On the negative end of the spectrum, hormonal changes may be associated with bone loss and nutrient deficiencies if you are not following your diet correctly or are skimping out on prescribed vitamins.

Hair Loss

Hair loss after gastric bypass surgery is one of the most common symptoms, affecting about one third of people between 3 to 6 months following surgery.

This hair loss is considered telogen effluvium and can be associated with the change in nutrition, hormonal levels, diet, stress and rapid weight loss.

Telogen Effluvium simply means that your hair shifts into the telogen phase, causing it to fall out due to the stress of surgery and corresponding weight loss.

The good news is that this lasts no longer than 6 months after surgery and will grow back.

There is not much to prevent this apart from increasing your protein intake, taking your post bariatric vitamins, and ensuring that you stick to your meal plans.


Gallstone formation can be common after gastric bypass surgery. This can occur in at least 35% of patients who undergo bariatric surgery. It is usually due to a change in bile acid circulation and the rapid weight loss that follows surgery.

The good news is that the risk of developing gallstones can be prevented by following a nutrient-rich diet and using prescribed medications like Ursodeoxycholic acid after gastric bypass surgery.

It is also recommended that patients do not skip meals and avoid overconsumption of foods high in saponins, such as beans, to prevent gallstones from developing.


It is important to remember that gastric bypass surgery has been one of the most effective treatments for obesity and has assisted many people in improving health.

Even though there are many risks involved, there are also many ways to mitigate and even prevent these side effects from occurring.

The bottom line is, if you decide to undergo surgery, you should follow your prescribed diet and supplement with additional vitamins and protein.

Luckily, Bariatric Fusion can assist you in obtaining all the nutrients you need to ensure optimal recovery.

From bariatric ADEK vitamins for duodenal switch patients to bariatric meal replacement/protein shakes.

Did you find our blog helpful? Then consider checking:

**This blog is for information and education purposes only. This information is not intended to substitute professional medical advice, diagnosis, or treatment. Please consult with your physician or another qualified health provider with any questions in regards to a medical condition. A qualified healthcare professional can best assist you in deciding whether a dietary supplement is suitable based on your individual needs.

Enjoy our recipe and articles?