Gastric Bypass, Diarrhea and Smelly Gas
Many people experience some degree of diarrhea and smelly gas -- malodorous flatulence -- after gastric bypass surgery. This is especially common during the first few months as their bodies adjust and heal. Although these symptoms are usually manageable with dietary changes and over-the-counter medications, discuss your symptoms with your surgeon before making changes to your treatment plan.
Digestion After Surgery
Gastric bypass surgery helps you lose weight by altering the anatomy of your digestive system. Your stomach is smaller after the procedure and food passes more quickly through your digestive system. As a result, your body absorbs fewer nutrients and your shortened bowel produces more gas and odors than before surgery.
To minimize the stress on your digestive system, follow your surgeon's meal plan instructions carefully. According to a report published in the September 2008 issue of "Surgery for Obesity and Related Diseases," most surgeons instruct patients to progress slowly during the first 8 weeks from liquids to pureed and soft foods before adding small amounts of solid foods.
- Gastric bypass surgery helps you lose weight by altering the anatomy of your digestive system.
- Your stomach is smaller after the procedure and food passes more quickly through your digestive system.
Early Postoperative Complications
Ileostomy Reversal Diet
Watery diarrhea and very foul-smelling gas occurring within the first 2 or 3 months after surgery may be due to Clostridium difficile colitis, according to a February 2008 report by the "American Society for Metabolic & Bariatric Surgery." Other symptoms may include fever, cramps in the abdomen and loss of appetite. C. difficile infections are generally treated with the antibiotic metronidazole (Flagyl).
A common cause of hospital-related diarrhea, C. difficile is spread through contact with anything contaminated by an infected person's stools, according to the Centers for Disease Control and Prevention. Risk factors include hospitalization, a recent course of antibiotics or abdominal surgery, including gastric bypass.
- Watery diarrhea and very foul-smelling gas occurring within the first 2 or 3 months after surgery may be due to Clostridium difficile colitis, according to a February 2008 report by the "American Society for Metabolic & Bariatric Surgery."
Long-Term Dietary Considerations
Diarrhea and flatulence usually improve as your body adjusts after gastric bypass surgery. After the early postoperative period, you will begin to eat small amounts of high-protein, low-carbohydrate, low-fat foods that give you the nutrients you need while losing weight. However, certain foods -- such as meat, beans, wheat, dairy products and vegetables -- may cause flatulence and diarrhea long after your body has healed. Keeping a food and symptom diary can help you pinpoint the foods that may be causing the problem.
- Diarrhea and flatulence usually improve as your body adjusts after gastric bypass surgery.
Why Do People Who Have Had Gastric Bypass Avoid Sugar?
Dumping syndrome frequently occurs in gastric bypass patients when they eat foods containing a large amount of sugar. The bowel responds to the high concentration of sugar by moving extra fluid into the digestive system. As a result, diarrhea often occurs within 30 to 60 minutes. Excess gas is also produced as bacteria feed on the sugar. Hormones are released during an occurrence of dumping syndrome, commonly resulting in dizziness, flushing, a drop in blood pressure and an increase in heart rate. Symptoms may range from mild to severe and generally last 1 to 2 hours.
- Dumping syndrome frequently occurs in gastric bypass patients when they eat foods containing a large amount of sugar.
- As a result, diarrhea often occurs within 30 to 60 minutes.
Certain eating habits can increase intestinal gas. Many surgeons advise patients to avoid activities such as drinking carbonated beverages, chewing gum or using a straw to prevent the introduction of excess air into the digestive system. Eating slowly and chewing your food thoroughly can improve digestion and may reduce excess intestinal gas.
Drinking liquids during meals can push foods through the digestive system too quickly. People who have undergone gastric bypass surgery are usually advised to stop all fluids before beginning to eat and to wait for roughly 30 minutes afterward before drinking again.
- Certain eating habits can increase intestinal gas.
- Drinking liquids during meals can push foods through the digestive system too quickly.
Over-the-Counter Medications and Supplements
Surgeons' guidelines vary, but many provide their patients with a list of over-the-counter remedies for symptoms related to their surgery. Your surgeon may suggest medications such as loperamide (Imodium) for diarrhea, simethicone (Gas-X) to reduce the amount of gas produced, and bismuth subgallate (Devrom) to reduce the bad odor of intestinal gas. Probiotic supplements may be helpful in managing symptoms after surgery because they replace natural digestive bacteria that can be lost during surgery or antibiotic treatment.
If you have abdominal pain, fever or other symptoms along with malodorous gas and diarrhea, contact your doctor immediately as you may have a complication that requires medical attention.
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Benefiber & Bloating
- American Society for Metabolic & Bariatric Surgery: Bariatric Surgery: Postoperative Concerns
- University of California, San Francisco: Recovering From Bariatric Surgery
- Journal of Gastrointestinal Surgery: Probiotics Improve Outcomes After Roux-en-Y Gastric Bypass: A Prospective Randomized Trial
- Surgery for Obesity and Related Diseases: ASMBS Allied Health Guidelines for the Surgical Weight Loss Patient
- Cleveland Clinic Center for Continuing Education: Antibiotic-Associated Diarrhea and Clostridium Difficile
- Midwest Bariatric Services: FAQs: Life After Surgery
- Centers for Disease and Prevention: Frequently Asked Questions about Clostridium difficile for Healthcare Providers
- University of Rochester Medical Center: Dumping Syndrome After Gastric Bypass Surgery
- Beamish AJ, Reinehr T. Should bariatric surgery be performed in adolescents?Eur J Endocrinol. 2017 Apr;176(4):D1-D15. doi:10.1530/EJE-16-0906
- American Society for Metabolic and Bariatric Surgery. Bariatric Surgery Procedures.
- Maciejewski ML et al. Bariatric Surgery and Long-term Durability of Weight Loss JAMA Surg. 2016 Nov 1;151(11):1046-1055. doi:10.1001/jamasurg.2016.2317
- Telem DA, Jones DB, Schauer PR, Brethauer SA, Rosenthal RJ, Provost D, Jones SB. (March 2020). Society of American Gastrointestinal and Endoscopic Surgeons (SAGES). Updated Panel Report: Best Practices for the Surgical Treatment of Obesity.
- Stahl JM, Malhotra S. Obesity Surgery Indications and Contraindications. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019. Updated May 2020.
- Kim RB. (Updated April 2020). Bariatric operations for management of obesity: Indications and preoperative preparation. Jones D, ed. UpToDate. Waltham, MA: UpToDate.
- Palermo M, Acquafresca PA, Rogula T, Duza GE, Serr E. Late surgical complications after gastric by-pass: a literature review. Arq Bras Cir Dig. 2015 Apr-Jun; 28(2): 139–143. doi:10.1590/S0102-67202015000200014
- University of Rochester Medical Center. (2020). Anastomotic Leak After Gastric Bypass Surgery
- Kim RB. (Updated May 2019). Laparoscopic Roux-en-Y gastric bypass. Jones D, ed. UpToDate. Waltham, MA: UpToDate.
- Wolfe BM, Kvach E, Eckel RH. Treatment of Obesity: Weight Loss and Bariatric Surgery. Circ Res. 2016 May 27; 118(11): 1844–1855.doi:10.1161/CIRCRESAHA.116.307591
- Monpellier VM, Antoniou EE, Aarts EO, Janssen IMC, Jansen ATM. Improvement of Health-Related Quality of Life After Roux-en-Y Gastric Bypass Related to Weight Loss. Obes Surg. 2017; 27(5): 1168–1173. doi:10.1007/s11695-016-2468-6
- Adams TD, Mehta TS, Davidson LE, Hunt SC. All-Cause and Cause-Specific Mortality Associated with Bariatric Surgery: A Review. Curr Atheroscler Rep. 2015 Dec; 17(12): 74. doi:10.1007/s11883-015-0551-4
- John Hopkins Medicine. Roux-en-Y Gastric Bypass Weight-Loss Surgery.
- Edholm D, Kullberg J, Karlsson FA, Haenni A, Ahlström H, Sundbom M. Changes in liver volume and body composition during 4 weeks of low calorie diet before laparoscopic gastric bypass. Surg Obes Relat Dis. May-Jun 2015;11(3):602-6. doi:10.1016/j.soard.2014.07.018
- UCSF Health. Recovery from Bariatric Surgery.
- Richardson WS, Plaisance AM, Periou L, Buquoi J, Tillery D. Long-term Management of Patients After Weight Loss Surgery. Ochsner J. 2009 Fall; 9(3): 154–159.
- UPMC. (2020). About Post-Surgery Bariatric Vitamins & Bariatric Supplements.
- Aminiana A, Changa J, Brethauera SA, Kimb JJ, American Society for Metabolic and Bariatric Surgery Clinical Issues Committee. ASMBS updated position statement on bariatric surgery in class I obesity (BMI 30-35 kg/m2). Surgery for Obesity and Related Diseases. 14 (2018) 1071-87.
- UCLA Health. Obesity Treatments. Gastric Bypass Surgery.
Marcy Brinkley has been writing professionally since 2007. Her work has appeared in "Chicken Soup for the Soul," "Texas Health Law Reporter" and the "State Bar of Texas Health Law Section Report." Her degrees include a Bachelor of Science in Nursing; a Master of Business Administration; and a Doctor of Jurisprudence.