Ulcerative Colitis vs. Proctitis: Similarities and Differences

Written by Stephanie Watson
Medically Reviewed by Melinda Ratini, MS, DO on March 25, 2025
10 min read

Proctitis is inflammation of the rectum, the last part of the large intestine that connects the colon to the anus. Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD). It causes inflammation in the inner lining of both the rectum and colon. The "-itis" in both proctitis and ulcerative colitis (UC) refers to inflammation. 

Proctitis can be its own condition when the cause is an infection or something else. Or it can be a form of ulcerative colitis that's only in the rectum, which is called ulcerative proctitis and is the most common type of proctitis. About 30% of people with UC have ulcerative proctitis. In 27% to 54% of people who are diagnosed with ulcerative proctitis, the inflammation spreads up the colon and progresses to ulcerative colitis. 

"While both conditions involve inflammation in the colon, they have key distinctions that affect diagnosis, treatment, and long-term management," says Mikhail Yakubov, MD, a gastroenterologist with Manhattan Gastroenterology in New York City. 

The exact cause of ulcerative colitis is unknown, but it likely stems from a problem with the immune system. Normally, the immune system releases white blood cells and inflammatory chemicals to fight the germs that cause infections. One theory is that in UC, the immune system tries to attack a virus or bacteria in the intestine. Instead, it mistakenly attacks healthy cells, causing inflammation and sores called ulcers in the colon lining.

UC sometimes runs in families, so genes may play a role. Researchers have found many gene changes that might increase the risk for this condition. Some of those genes affect the lining of the intestines. Others are involved in the immune system response. 

Genes likely increase the risk for ulcerative colitis, but then something in the environment sets off the disease. Pollution, certain diets, and medicines are all possible triggers, but none of them are proven.

Both ulcerative colitis and the other type of IBD, Crohn's disease, cause proctitis. About 30% of people with IBD have proctitis.

Ulcerative colitis and Crohn’s disease are the most common causes of proctitis. Other possible causes include:

Sexually transmitted diseases (STDs). The bacteria or viruses that cause gonorrhea, genital herpes, syphilis, and chlamydia can get into the rectum during anal sex and cause inflammation.

Radiation therapy. People who have radiation therapy to their pelvis to treat prostate or gynecologic cancer can develop inflammation in the rectum. 

Poor blood flow. Ischemic proctitis is a type caused by reduced blood flow to the rectum. It most often affects older adults.

Antibiotics. When you take these medicines to control an infection, they can change the balance of good and bad bacteria in your gut. Too much of the harmful bacteria Clostridioides difficile (C. diff) grows and crowds out more helpful bacteria. C. diff bacteria irritate the intestine wall.

Ostomy surgery. Diversion proctitis is a type that happens after ostomy surgery. An ostomy surgery is a treatment for diseases like colon cancer and IBD. During the procedure, the surgeon attaches the end of the intestine to an opening in the belly wall. Wastes pass out of the body through this opening instead of through the rectum. Some people who don't have their rectum removed during the surgery develop proctitis.  

Allergies to food proteins. Some infants are allergic to proteins in cow's milk or soy-based formula. Some may also be sensitive to breast milk if the mother consumes dairy products. Exposure to these proteins causes inflammation in the colon and rectum.

Because ulcerative colitis and proctitis inflame the rectum, they have many of the same symptoms:

  • Bleeding from the rectum when you poop
  • Pain in the rectum 
  • Belly pain and cramping
  • Pain when you poop
  • Diarrhea that may contain blood or mucus
  • An urgent need to poop
  • Feeling like you have to poop but then nothing comes out 

Ulcerative colitis also causes these symptoms:

  • Tiredness
  • Fever
  • Weight loss
  • Nausea
  • Slow growth in children

UC symptoms can be mild, moderate, or severe. Symptoms often come and go. During a remission you might go weeks, months, or years without symptoms. Then symptoms come back, or relapse.

 

Diagnosing UC and proctitis starts by having a discussion with your doctor about your symptoms, medical history, and family medical history. If your doctor suspects proctitis, they might also ask:

  • Do you have an STD or are you at risk for one?
  • Do you have a personal or family history of IBD?
  • Have you taken antibiotics recently?

These tests help doctors diagnose ulcerative colitis and proctitis:

Blood tests. Testing a sample of your blood can show anemia (low red blood cells), which may be a sign of bleeding in your colon or rectum. Blood tests also detect inflammation and infections.

Stool tests. Your doctor might ask for a sample of your poop to check for infections or bleeding.

Endoscopic tests. In these tests, a flexible tube with a light and camera on the end goes into your colon so your doctor can see inside your colon. 

  • Colonoscopy shows the whole colon and rectum
  • Flexible sigmoidoscopy shows just the lower part of the colon and rectum

During these tests the doctor can remove a sample of tissue to biopsy, which can confirm the diagnosis.

These are some other tests your doctor might order if they suspect ulcerative colitis:

Imaging tests like these show whether there is inflammation in the colon: 

  • Computed tomography (CT) uses X-rays and a computer to create detailed pictures of your colon.
  • Magnetic resonance imaging (MRI) uses powerful magnets, radio waves, and a computer to take pictures.
  • X-ray takes images of your colon using small doses of radiation. 

These tests can help your doctor diagnose proctitis:

Digital rectal exam. The doctor inserts a gloved finger into the rectum to check for abnormal areas.

Urine tests. A urine test may be able to show whether you have an STD like chlamydia or gonorrhea that can cause proctitis.

Rectal culture. The doctor takes a swab from the inside of your rectum and tests it for germs that cause infections.

Flexible sigmoidoscopy. Viewing the lower part of your colon and rectum through a flexible tube is also a way to test for proctitis.

Proctoscopy. Your doctor uses a very short scope with a light and camera on the end to examine just your rectum and possibly take a biopsy sample.

Ulcerative colitis treatment

In UC, a problem with the immune system causes inflammation in the colon. "To treat it requires medication that helps regulate the inflammation," says Alexandra Gutierrez, MD, director of the Inflammatory Bowel Disease Center in Medicine at Columbia University Irving Medical Center in New York City. Reducing inflammation gives your colon a chance to heal.

A few medicines treat ulcerative colitis. Each one reduces inflammation in a different way. 

Anti-inflammatory drugs lower inflammation generally in the body. They include: 

  • 5-aminosalicylates (5-ASAs) like sulfasalazine (Azulfidine) and mesalamine (Apriso, Asacol HD, Delzicol, Lialda, Pentasa)
  • Corticosteroids

Immunosuppressant drugs calm your immune system to bring down inflammation. Examples are: 

  • 6-mercaptopurine (Purinethol, Purixan)
  • Azathioprine (Azasan, Imuran)
  • Cyclosporine (Gengraf, Neoral, Sandimmune)
  • Methotrexate (Jylamvo, Trexall, Xatmep)

Biologic drugs block specific immune system proteins that produce inflammation. These medicines typically come as an injection or infusion. They're a treatment for moderate-to-severe UC. They're also prescribed when other treatments don't work well enough. 

Biologics prescribed for ulcerative colitis include:

  • Tumor necrosis factor (TNF) inhibitors like adalimumab (Humira), golimumab (Simponi), and infliximab (Remicade)
  • Guselkumab (Tremfya)
  • Mirikizumab (Omvoh)
  • Risankizumab (Skyrizi)
  • Ustekinumab (Stelara)
  • Vedolizumab (Entyvio)

Small molecule drugs also target parts of the immune system that cause inflammation, but they come as pills. This group of medicines includes:

  • Janus kinase (JAK) inhibitors like filgotinib (Jyseleca), tofacitinib (Xeljanz), and upadacitinib (Rinvoq)
  • Sphingosine-1-phosphate (S1P) receptor modulators: etrasimod (Velsipity) and ozanimod (Zeposia)

About one-third of people with UC won't improve enough with medication. In that case, the next step may be colectomy – surgery to remove the colon.

Proctitis treatment

Sometimes proctitis improves on its own, but not always. "Treating the cause of the proctitis is key," says Gutierrez. The choice of treatment depends on whether UC, an infection, or something else caused the inflammation.

IBD. Some of the same anti-inflammatory and immune-suppressing medicines that doctors prescribe for ulcerative colitis also treat proctitis. "First-line therapy is typically topical mesalamine suppositories or 5-ASA enemas, which directly reduce inflammation in the rectum," says Yakubov. If symptoms don't improve, steroids may be added. Severe cases of proctitis may need treatment with oral immunosuppressants or biologic drugs, similar to UC. 

Infection. Treating the infection should clear up proctitis too. Antibiotics treat bacterial infections like chlamydia and gonorrhea. Antiviral medicines treat viral infections like herpes. It's important for your sexual partners to also get screened and treated if an STD caused your proctitis.

Radiation therapy. Proctitis should improve within a few weeks after you finish radiation treatment. Until then, you can try anti-inflammatory suppositories, enemas, or stool softeners to reduce irritation in the rectum. If rectal bleeding is severe, a minimally invasive procedure can stop it.

Ostomy surgery. If proctitis started after ostomy surgery, you may need another procedure to close the ostomy and reconnect your intestines to your rectum. When a second surgery isn't an option, doctors prescribe medicines like suppositories and enemas to treat diversion proctitis.

Whether you have ulcerative colitis, proctitis, or both conditions, caring for yourself is important. 

Tips for living with UC vs. proctitis

While you take medicine to treat UC or proctitis, lifestyle changes like diet, exercise, and stress management can help you get a better handle on your symptoms. The advice is the same for UC and proctitis.

Follow a gut-friendly diet. No specific diet causes ulcerative colitis or proctitis, but you may find that certain foods make your symptoms better or worse. "Avoiding spicy foods, caffeine, alcohol, and high-fat meals may reduce irritation," says Yakubov. Keeping a diary can help you identify which foods bother you. Some common culprits are dairy foods like milk and cheese, raw fruits and vegetables, and nuts and seeds.

Eat smaller meals. Having three big meals can be hard on your digestive system. Instead, try to eat several small meals or snacks throughout the day.

Choose the right type of fiber. Fiber comes in two forms. Insoluble fiber, found in whole grains, fruits, and vegetables, is the type that doesn't dissolve in water. Some people with IBD need to limit insoluble fiber because it makes their symptoms worse during a flare. Soluble fiber from foods like bananas, potatoes, and oats adds bulk to your poop, which might help with diarrhea.

Drink more water. Diarrhea can dehydrate you. Make sure to drink enough water to stay hydrated. Avoid alcohol because it makes diarrhea worse. Also skip sodas, which cause gas.

Try pelvic floor physical therapy. A physical therapist can teach you exercises to strengthen your pelvic floor muscles. This treatment can help with rectal urgency.

Practice safe sex. If proctitis is from an STD, wearing condoms can help prevent you from getting reinfected.

Relieve stress. Living with a chronic disease can be stressful. Though stress doesn't cause ulcerative colitis or proctitis, it could make symptoms worse. One reason is that stress may increase inflammation. 

Try techniques like these when you're feeling stressed:

  • Meditation
  • Progressive muscle relaxation — alternately tense and release each group of muscles from your toes to your head
  • Exercise
  • Deep breathing
  • Yoga

Ulcerative colitis is a type of IBD. It causes inflammation in the lining of the rectum and colon. Proctitis is inflammation that's just in the rectum. It can be a form of UC, or it can happen for other reasons. Medicines that reduce inflammation and calm the immune system treat both UC and proctitis. Some of the same anti-inflammatory medicines work for both conditions. Diet and stress relief are also important for managing both conditions. 

Is ulcerative proctitis the same as ulcerative colitis?

Ulcerative colitis is a type of inflammatory bowel disease (IBD). Proctitis can be a form of UC, but it can have other causes as well, such as infections, radiation therapy, or antibiotics. Ulcerative colitis causes inflammation in the lining of the colon and rectum. In proctitis, inflammation is only in the rectum. 

Is ulcerative proctitis the same as erosive proctitis?

Ulcerative proctitis is a form of ulcerative colitis that affects just the rectum. Erosive proctitis is damage to the rectum that can happen from anal sex.

Can you have proctitis without ulcerative colitis?

Yes. Ulcerative colitis is the most common cause of proctitis, but it's not the only cause. You can get proctitis from a STD or other infection, medicine, radiation therapy, or bowel surgery.