IBD Complications: What You Need to Know

by Jennifer Mitchell Wilson B.S. Dietetics, Dietitian, Health Professional

Inflammatory bowel disease (IBD), comprised primarily of ulcerative colitis (UC) and Crohn’s disease, affects an estimated 1.6 million Americans. Adequately treating these conditions involves providing patients with a remission of disease and its painful symptoms.

However, not all treatments work for everyone or continue to work throughout the course of the disease. Those issues, among others, can leave patients with active flare-ups.

When an active flare-up of IBD occurs, there is a chance of additional complications arising, as well. A few of the most common complications are:


Intestinal obstruction is the most common complication of Crohn’s disease. It occurs when swelling or scarring in the intestine thickens the bowel wall. This results in a narrower area through which material can move. Symptoms often present with crampy abdominal pain, vomiting, and bloating. Medications to reduce the swelling and inflammation are usually the first line of defense in treating an obstruction. If the issue is not resolved with medications or is severe, surgery may be needed.


More common in Crohn’s Disease, a stricture is a scar that forms after repeated inflammation. Depending on where the stricture occurs, it may need to be removed to prevent bowel blockage or obstruction. If a stricture is found in a person with UC (which is rare) it should be considered malignant until proven otherwise through appropriate testing. Symptoms vary depending on the severity, but if it's an obstruction or partial obstruction the symptoms (as noted above) will be crampy abdominal pain, vomiting, and bloating.

Fistula and abscess

Fistulas and abscesses are also more common in Crohn’s disease, but can occur in as many as 20 percent of UC patients. Abscesses are localized pockets of pus that are caused by bacterial infection. Fistulas occur when deep sores or ulcers turn into abnormal passages. These passages can connect different parts of the intestine or may even connect to surrounding organs like the bladder or vagina. Depending on their severity, abscesses and fistulas may both be treated with antibiotics or a combination of antibiotics and surgery.

Toxic megacolon

Toxic megacolon is the most severe complication of IBD, and is life threatening. Although rare, this condition is more frequently seen in UC. Toxic megacolon occurs when the colon loses its ability to move gas along and to contract properly. This causes severe abdominal distention, high fever, and extreme pain and tenderness in the abdomen. Blood work may also show a high white count indicative of active infection. Treatment must be prompt in order to reduce the pressure within the bowel and prevent rupture. In some instances, the excess air can be suctioned out through a nasogastric tube, or surgery might be required.


Bowel perforation or rupture occurs when chronic inflammation or ulceration leads to a weakness in the bowel wall that causes a hole to form. This is especially dangerous because it causes bacteria and fecal matter to spill into the abdomen, which can lead to a life-threatening infection. In UC, perforation is most often caused by toxic megacolon; in Crohn’s disease, it may occur because of an abscess or fistula. A perforated bowel requires immediate surgical repair.


Malignancy or cancerous lesions are rare, and the overall risk for developing colon cancer in the general population is only three to six percent. For UC patients the risk is slightly higher, at an incidence rate of five to eight percent in the 20 years after diagnosis. Discuss with your physician any family history of colon cancer and what additional screening might be recommended if have if you have UC.

While most complications are rare, it is important to be aware of them and of the potential symptoms mentioned above. Keeping your disease in remission by following your doctor’s instructions regarding treatments and medication is key. Be sure to follow up with your gastroenterologist and keep your appointments, even if you are feeling well, as they can often help to catch flare-ups before they become severe.

Jennifer has a bachelor's degree in dietetics as well as graduate work in public health and nutrition.She has worked with families dealing with digestive disease, asthma and food allergies for the past 12 years.Jennifer also serves on the Board of Directors for Pediatric Adolescent Gastroesophageal Reflux Association (PAGER).

Jennifer Mitchell Wilson
Meet Our Writer
Jennifer Mitchell Wilson

Jennifer Mitchell Wilson is a dietitian and mother of three girls. Two of her children have dealt with acid reflux disease, food allergies, migraines, and asthma. She has a Bachelor of Science in dietetics from Harding University and has done graduate work in public health and nutrition through Eastern Kentucky University. In addition to writing for HealthCentral, she does patient consults and serves on the Board of Directors for the Pediatric Adolescent Gastroesophageal Reflux Association.