Left-sided ulcerative colitis can cause pain in your abdomen or rectum along with other symptoms. Treatment typically involves medication to reduce inflammation.

Ulcerative colitis is a condition that causes your colon or parts of it to become inflamed. In left-sided ulcerative colitis, inflammation occurs only on the left side of your colon. It’s also known as distal ulcerative colitis.

In this form of ulcerative colitis, inflammation stretches from your rectum to your splenic flexure. The splenic flexure is the name of a bend in the colon, near your spleen. It’s located on the left side of the abdomen.

Other types of ulcerative colitis include:

  • proctitis, in which inflammation is limited to the rectum
  • pancolitis, which causes inflammation throughout the whole colon

Generally, the more of your colon that’s affected, the more symptoms you experience.

Diarrhea is the most common symptom of ulcerative colitis. Sometimes, your stool may also have streaks of blood.

Damage and irritation to your rectum can cause you to feel like you’re constantly needing to have a bowel movement. However, when you go to the bathroom, the amount of stool is usually small.

Other symptoms of ulcerative colitis include:

  • abdominal pain or rectal pain
  • fever
  • weight loss
  • constipation
  • rectal spasms

Bloody stools can be a sign of serious damage to the colon. Blood in your stool may be bright or dark red.

If you see blood in your stool, call your doctor. If there’s more than a small amount of blood, seek emergency medical attention.

Doctors don’t know what exactly causes ulcerative colitis. One theory is that it’s due to an autoimmune disorder that causes inflammation in your colon.

It’s believed ulcerative colitis occurs due to a number of factors. These include:

  • genetics
  • abnormal immune response
  • microbiome
  • environmental factors

Your doctor may identify the type of colitis you have with a procedure known as an endoscopy. In an endoscopy, they use lighted cameras to view the inner lining of your colon.

Your doctor can identify the degree of inflammation by looking for:

  • redness
  • edema
  • other irregularities in the lining of the colon

If you have left-sided colitis, the lining of your colon will start to look normal again once your doctor has navigated past the splenic flexure.

Treatment recommendations for ulcerative colitis can change depending on how much of your colon is affected. However, your doctor may prescribe the following treatments:

5-ASA medication

A medication known as 5-aminosalicylic acid, or 5-ASA, is a common treatment for ulcerative colitis.

5-ASA medications can be taken orally or applied topically. They can reduce the incidence of inflammation in your bowel.

5-ASA is also available as a suppository or enema. If you have left-sided ulcerative colitis, your doctor will likely prescribe an enema. A suppository wouldn’t reach enough of the affected area.

Oral corticosteroids

If your symptoms don’t respond to 5-ASA, your doctor may prescribe oral corticosteroids. Oral corticosteroids can reduce inflammation. They’re often successful when taken with 5-ASA medications.

Biologics and immunomodulators

If your symptoms are moderate to severe, your doctor may prescribe a biologic drug. These are antibodies that target inactivate immune system proteins known to cause ulcerative colitis inflammation.

They’re a long-term treatment that can help prevent flareups.

Current guidelines suggest that the following options may be the most effective:

Another type of drug, known as immunomodulators, may also help. A doctor may prescribe these alongside other options. They include:

Long-term treatment can reduce the risk of a flare and lessen the need for steroid medications, which can have adverse effects.

JAK inhibitors

Janus kinase inhibitors (JAK Inhibitors) are small compounds that are broken down in the digestive system. They’re then absorbed into the bloodstream.

They work by blocking pathways of inflammation in the body. They act faster than some other medications like thiopurines.

The Food and Drug Administration (FDA) has approved two JAK inhibitors for the treatment of moderate to severe ulcerative colitis:

  • tofacitinib (Xelianz), which is available in tablet form
  • upadacitinib (Rinvoq), which is available in tablet form for the treatment of ulcerative colitis when one or more TNF blockers have been used and were unsuccessful or poorly tolerated


In severe, rare instances, you may require hospitalization to treat your symptoms. If you’re hospitalized, you may receive intravenous (IV) steroids or other IV medications that can help stabilize your condition.

Sometimes, your doctor may recommend removing the affected portion of your colon. This is usually recommended only if you have severe bleeding or the inflammation has caused a small hole in your colon.

More research needs to be done on the benefits of natural treatments and remedies for ulcerative colitis. But there are some options that may help you manage the condition.

These include:

Talk with your doctor before starting any of these treatments to make sure they’re safe and right for you.

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