Collagenous Colitis: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Collagenous Colitis?
A gastroenterologist, a doctor for the digestive system, usually treats collagenous colitis. Collagenous colitis is one of two types of microscopic colitis. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is collagenous colitis?
Collagenous colitis is one of two types of microscopic colitis. Microscopic colitis is a chronic disease. In it, abnormal reactions of the immune system cause inflammation on the inner lining of the colon. Doctors can only see this inflammation by looking at colon tissue under a microscope.
In collagenous colitis, the layer of collagen under the colon lining is thicker than normal. The colon lining may also contain more white blood cells than normal. Doctors call both types microscopic colitis. They have the same symptoms and treatments.
Microscopic colitis is a type of inflammatory bowel disease (IBD). Unlike the other types of IBD, it does not increase your risk of developing colon cancer.
Symptoms
Symptoms may include the following.
- Chronic, watery diarrhea without blood is the most common symptom
- Diarrhea that occurs at night
- Pain in the abdomen
- An urgent need to have a bowel movement
- Fecal incontinence
- Weight loss
- Fatigue, or feeling tired
Symptoms may start suddenly. They may also begin slowly and get worse over time. Many people with this disease have four to nine bowel movements a day. Some people may have more than 10 a day.
You may have remission. These are times when you have fewer symptoms or symptoms disappear. After a period of remission, you may have a relapse. This is a time when symptoms return or worsen.
Causes and who gets it
Doctors are not sure what causes microscopic colitis. Abnormal reactions of the immune system may play a part. Some immune disorders make it more likely. Examples are celiac disease, rheumatoid arthritis, and type 1 diabetes. Research suggests certain genes increase the chance of getting the disease.
Taking certain medicines may raise the risk of getting the disease. These include NSAIDs, PPIs, and SSRIs, a type of antidepressant. They also include hormone replacement therapy and oral contraceptives. Beta blockers are medicines that slow your heart rate. Statins are medications to lower cholesterol.
Studies suggest people who smoke cigarettes are more likely to get the disease. Smokers who get the disease tend to get it at a younger age.
Anyone can get the disease. But it is more common in older adults and in women. The average age at diagnosis is 60 to 65 years. However, it may occur in people of any age, including children. Research suggests it is three to nine times more common in women than in men.
How doctors diagnose it
The inflammation in this disease can be seen only by looking at colon tissue under a microscope. So a doctor needs a small sample of colon tissue to find it.
Treatment
To treat microscopic colitis, your doctor may recommend quitting smoking, if you smoke. Your doctor may also change any medicines you take that could be causing the disease or making your symptoms worse. Changing what you eat and drink may help improve symptoms.
Medicines most often treat microscopic colitis well. Doctors prescribe medicines to improve symptoms and bring on remission. The steroid budesonide is the medicine most often used. Other choices include medicines that slow diarrhea. Some bind bile acids. Others quiet the immune system. Do not stop or change a medicine on your own. Your doctor decides which one is right for you.
Doctors rarely recommend surgery. It may be an option if symptoms are severe and do not get better with medicines.
When to see a doctor
Severe diarrhea may lead to weight loss and dehydration. In rare cases, it may cause serious problems, such as ulcers or perforation of the colon. Call 911 or go to the emergency room if you have severe belly pain or pressure. Call 911 or go to the emergency room if you have severe or persistent vomiting or diarrhea.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A doctor like this can review the medicines you take, since changing them is one possible treatment.
Common questions
Is collagenous colitis the same as microscopic colitis?
Collagenous colitis is one of the two types of microscopic colitis. Doctors call both types microscopic colitis. They have the same symptoms and treatments.
Does collagenous colitis raise the risk of colon cancer?
No, unlike the other types of IBD, microscopic colitis does not increase your risk of colon cancer.
Can collagenous colitis symptoms go away?
Symptoms can go away for a time. This is called remission. After remission, you may have a relapse. This is a time when symptoms return or worsen.
Who is most likely to get collagenous colitis?
Older adults and women are more likely to get it. But anyone can get it. The average age at diagnosis is 60 to 65 years.
Do medicines help collagenous colitis?
Yes, medicines most often treat microscopic colitis well. The steroid budesonide is the medicine most often used.
Sources
- NIDDK - Definition & Facts of Microscopic Colitis
- NIDDK - Symptoms & Causes of Microscopic Colitis
- NIDDK - Treatment for Microscopic Colitis
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
