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Bariatric Surgery

Side Effects

Possible side effects that patients may experience after weight-loss surgery include:

Nausea and Vomiting

Patients may have a few episodes of nausea, vomiting and abdominal discomfort after surgery. This usually occurs in the first 2 or 3 months after surgery, as patients are getting used to their new diet and eating habits.

Nausea, vomiting or abdominal discomfort are usually due to one or more of the following:

  • eating too quickly
  • taking bites that are too large (e.g., larger than the suggested pencil -eraser size)
  • not chewing well enough before swallowing (we recommend chewing each bite 15 times)
  • consuming too large a volume at one time (remember, the stomach pouch is only 1 ounce - the size of a thumb)
  • eating foods that are too dry or tough

Patients are advised of the following:

  • Pay attention to signs of fullness, such as chest discomfort, pressure or pain, and stop eating/drinking immediately when these occur. Ignoring these signals and eating less than “mindfully” after bariatric surgery puts you at higher risk for vomiting and other complications.
  • The slower you eat, the more time your body has to recognize and send a signal of fullness to your brain, notifying you to stop before "overeating."
  • Persistent vomiting or vomiting with abdominal pain may warrant an immediate call to our office.
  • Nausea or vomiting can be caused by dehydration. It is very important to maintain adequate fluid intake.
  • Patients with post-nasal drip may have episodes of nausea in the early period after surgery if they swallow the secretions. Over-the-counter medications may help dry up the sinuses and alleviate symptoms due to post-nasal drip.
  • Eating certain foods, such as cauliflower or broccoli, can cause abdominal pain due to gas, bloating and cramping. If this occurs, try eliminating certain foods from the diet or prepare the food a different way.

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It is important to drink about 2 liters of liquid a day during the first few months of rapid weight loss after gastric bypass surgery. Drinking this much fluid can be difficult during the first few weeks after surgery. However, dehydration can lead to nausea and persistent vomiting. Also, persistent vomiting can lead to dehydration and electrolyte imbalance.

Dehydration and vomiting can become a vicious cycle and lead to vitamin deficiencies. It may even be necessary to return to the hospital to receive IV fluids and vitamins.

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Food Intolerance

Patients may be intolerant to some foods after gastric bypass surgery. Eating smaller portions, eating more slowly, chewing foods well and avoiding high-sugar foods can resolve problems with food intolerance. Also, taking a step back (such as to a liquid diet) can help. Patients need to learn to stop when they feel satisfied. The one additional bite is enough to cause problems. Follow these precautions regarding specific foods:

  • Foods that are dry (roast beef, turkey, other meats), sticky (peanut butter), gummy (fresh bread), or stringy (chicken, celery, fibrous fruit, and vegetables) present the biggest problems.

  • Most patients have little difficulty with meats, but some patients find that tough steak, pork, and chicken can be difficult to tolerate after gastric bypass surgery. This is because the connective tissue in the meat may not break down (it remains 'stringy’), no matter how much it is chewed. If the small stomach outlet gets plugged, vomiting will result. Patients should avoid tough meats (steak, pork) for the first few months. Also, cutting meat into pieces the size of a pencil eraser can make meat more tolerable. We recommend trying tender meats such as filet mignon and Delmonico steak.

  • Bread/pasta/rice – Fresh bread, pasta, and rice tend to become “gummy” and cause blockage of the stomach pouch outlet. Toasted bread, crackers and tortilla shells (soft and hard) are more tolerable. Avoid eating too much starch and carbohydrate.

  • Vegetables like cauliflower and broccoli may cause gas and abdominal cramping.

  • Approximately 1% of patients develop a new intolerance to milk and milk products (lactose intolerance). Symptoms can include gas, bloating, cramps and diarrhea. These symptoms commonly diminish over time and with slower consumption of lactose-containing foods or beverages. If this occurs, try low-fat milk (1% or skim milk); if this does not relieve symptoms, try lactose-free milk or soy milk. Lactase enzyme pills (Lactaid) may be helpful.

  • After gastric bypass surgery, patients will feel the effects of alcohol more quickly and after less alcohol than before surgery. Please be aware of increased sensitivity to alcohol, especially if you are the designated driver!

  • Patients should not try to eat steak or pizza for the first 2 or 3 weeks after surgery; these foods will cause you to get sick.

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Dumping Syndrome

A condition known as “dumping syndrome” can occur as the result of rapid emptying (“dumping”) of stomach contents into the small intestine. This is triggered when too much sugar or very greasy (fried) foods are consumed.

Although it is not considered a serious risk to health, the symptoms of dumping syndrome can be extremely unpleasant. They include nausea, weakness, sweating, faintness, tiredness, diarrhea, rapid heart rate and stomach cramping after eating. Patients usually say the symptoms make them feel “like I want to lie down and die for a half hour.”

Some patients are unable to eat any form of sweets after gastric bypass surgery without experiencing symptoms of dumping syndrome. We consider this to be an advantage of gastric bypass surgery more than a complication. Patients with purely restrictive weight-loss surgeries (adjustable band) do not experience dumping syndrome and can tolerate high-calorie foods such as milk shakes and sweets. Because these foods cause symptoms after gastric bypass surgery, patients tend to avoid them and to follow a healthier diet.

The best way to avoid dumping syndrome is to avoid sugary and fatty foods, including maple syrup, candies, fruit juices, ice cream, milk shakes, brownies, BBQ sauce, high-sugar cappuccinos, french fries, fried chicken, and other foods that have high sugar or grease content. Artificial sweeteners typically do not cause dumping syndrome.

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Changed Bowel Habits

After gastric bypass surgery, patients may have smaller and fewer bowel movements, and constipation is quite common. This is especially true in women and when guidelines are followed for iron supplementation.

Increased fluid intake, eating more vegetables and fresh fruits (blueberries), and exercising more may alleviate symptoms.

Taking a fiber supplement or laxatives may be necessary if symptoms persist.

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Transient Hair Thinning

About half of women who have undergone gastric bypass surgery notice thinning of their hair. This usually occurs between months 2 and 10 after surgery.

Thinning may be minimized by maintaining adequate protein intake, taking daily multivitamins, and possibly by addition of zinc and biotin supplements.

It is important to remember that this phase is temporary and hair usually comes back to normal. Some patients who had thin hair before surgery may find wearing a wig necessary during this time.

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Many obese women have trouble with fertility and regular menstrual cycles. As weight loss occurs, this situation may change quickly. Women get more regular periods and can become more fertile with weight loss.

Rapid weight loss and nutritional deficiencies can harm a developing fetus, resulting in birth defects. Thus, it is very important for women of reproductive age to avoid becoming pregnant during the first 12 to 18 months after surgery.

Women of childbearing age must use some form of birth control during this rapid weight loss phase. Barrier contraceptives (condom, diaphragm) may be more effective than oral contraceptives as the absorption of birth control pills mat not be the same after surgery.

After weight loss has stabilized, it is possible to have a healthy pregnancy:

  • Discuss this with your obstetrician and surgeon.
  • You must take extra vitamins before becoming pregnant and get adequate nutrition during pregnancy.
  • Patients who develop food intolerance during pregnancy due to severe nausea and vomiting may require nutrition through an IV.

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Cold Intolerance

Many patients notice that they feel “cold” after they begin losing weight. This is due to a change in metabolism and a loss of insulating body fat.

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Caution with Upper Endoscopy

After gastric bypass surgery, the anatomy of the gastrointestinal (GI) tract changes permanently. Access to the disconnected stomach (gastric remnant) and duodenum may be required in the future for tests like endoscopic gastroduodenoscopy (EGD) or endoscopic retrograde cholangiopancreatography (ERCP) to diagnose problems such as ulcers, bleeding, cancer, or bile duct problems.

Because access to the disconnected portion of the GI tract is very difficult with the current technology, laparoscopic surgery may be needed to assess this part of the GI tract.

There is no problem performing a colonoscopy after gastric bypass surgery.

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Plastic Surgery

Many patients have excess skin on their body after significant weight loss. This excess skin can be anywhere, but the most common place is the abdomen, thighs, breasts and upper arms. Some patients may not like how they look naked after weight loss surgery.

The excess skin can occasionally cause problems such as rash, functional limitations and cosmetic discomfort. Patients who experience successful weight loss with significant areas of redundant skin tissue often request body contouring by plastic surgery.

Plastic surgery to remove the excess tissue may occasionally be covered by health insurance companies. However, it may be difficult to obtain insurance coverage for plastic surgery and it may be necessary to pay out-of-pocket.

We recommend that you wait to make this decision until at least 18 months to 2 years after surgery, or until your weight has reached a plateau and you are in an exercise program to tone muscle.

A plastic surgeon speaks at our support group meetings a number of times throughout the year.

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