What Is Crohn's Disease?

This informational guide, part of POPSUGAR's Condition Center, lays out the realities of this health concern: what it is, what it can look like, and strategies that medical experts say are proven to help. You should always consult your doctor regarding matters pertaining to your health and before starting any course of medical treatment.

More than half a million Americans have Crohn's disease, a chronic condition that causes inflammation in the gastrointestinal tract, according to the National Library of Medicine. "Crohn's disease is an abnormal response of the immune system against the body's intestines," says Randy Meisner, MD, a gastroenterologist at Corewell Health. "It can lead to a lot of problems." Symptoms of Crohn's disease often show up in a person's late teens or 20s and can be life altering. While Crohn's isn't as well-known to the general public as some other digestive diseases like IBS, it can be serious. That's why being aware of Crohn's disease, along with its symptoms and treatment options, is so important.

Crohn's disease is a chronic disease that causes inflammation and irritation in your digestive tract, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Crohn's usually impacts the small intestine and beginning of the large intestine, but it can affect any part of the digestive tract, including the mouth and anus.

"It can interfere with absorbing nutrition. It can cause bleeding and ulcers as well as low blood counts," says Ellen Stein, MD, a gastroenterologist and associate professor at Rutgers Robert Wood Johnson Medical School. "Some people have very mild symptoms, and some people can get very, very sick."

There is a range of potential symptoms with Crohn's disease. According to the US National Library of Medicine, these can include:

"Usually, a patient will have more than one symptom or laboratory abnormality, but sometimes patients with mild disease can present with just one," Dr. Meisner says.

Some symptoms of Crohn's disease can overlap with those of fellow inflammatory gastrointestinal disease IBS, but Dr. Stein says testing can help reveal what's making a patient sick.

Researchers aren't entirely sure what causes Crohn's disease, but the NIDDK says there are a few factors thought to be linked to the condition:

"Crohn's disease is treatable, but it's not curable," Dr. Meisner says. There's no single treatment that works for everyone with Crohn's disease, but there are options, he says.

There are a range of medications that can help manage Crohn's disease. Per the NIDDK, those include:

Some patients with Crohn's disease may need to go on bowel rest for a few days to several weeks during a flare of symptoms. The NIDDK says that involves only drinking certain liquids or not eating or drinking anything.

Some patients may need surgery to help with complications of the disease, including fistulas, intestinal blockage, and severe bleeding. That can include small bowel resection, where part of the small intestine is removed; subtotal colectomy, where part of the large intestine is removed; proctocolectomy, which removes the entire colon and rectum; and ileostomy, which is an opening created in the abdomen that waste is removed from, usually via an ostomy pouch, the NIDDK says.

"Most people need medications to help manage their inflammation and their Crohn's disease," Dr. Stein says. "Most patients will need to continue their medication over time to maintain their remission and keep from having new flares of symptoms."