Pseudomembranous Colitis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Pseudomembranous Colitis?
A primary care doctor usually treats mild cases; severe or recurring infections are referred to a gastroenterologist. 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 it is
Pseudomembranous colitis is swelling and irritation of the large intestine, named for patches called pseudomembranes that form on the inflamed lining. It is most often caused by bacteria called Clostridioides difficile, or C. diff.
Symptoms
The most common sign is watery diarrhea that may contain blood or mucus, often with belly cramps, fever, and nausea. Symptoms usually start during or shortly after antibiotic use, and severe cases can cause dehydration.
Causes and who gets it
Antibiotics can wipe out helpful gut bacteria, letting C. diff grow out of control and release toxins that damage the colon. Risk is highest in people who recently took antibiotics, stayed in a hospital or nursing home, or have a weak immune system.
How doctors diagnose it
A doctor will ask about recent antibiotic use and symptoms. The main test is a stool sample checked for C. diff toxins; blood tests or a CT scan may also help.
Treatment
The first step is to stop the triggering antibiotic. Doctors then prescribe antibiotics that target C. diff, such as vancomycin or fidaxomicin. Repeat infections may need longer treatment or a fecal microbiota transplant; severe cases sometimes need hospital care.
When to see a doctor
Anyone with watery diarrhea after antibiotics should contact a doctor, especially with fever, belly pain, blood in the stool, or signs of dehydration. Severe or worsening symptoms need prompt attention.
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 charges more and often works alongside insurance. Both can handle mild cases and will refer to a gastroenterologist if needed.
Common questions
Is pseudomembranous colitis contagious?
The infection itself can spread. C. diff germs pass in stool and can survive on surfaces for a long time. Washing hands with soap and water and cleaning surfaces with bleach-based products helps stop the spread.
Can it go away without treatment?
Mild cases sometimes improve once the triggering antibiotic is stopped. Even so, many people still need specific antibiotics to clear the infection. Doctors generally recommend treatment rather than waiting. Untreated infections can become serious.
Why do antibiotics cause this problem?
Antibiotics kill bacteria, including the helpful ones that live in the gut and keep harmful germs under control. When those helpful bacteria are reduced, C. diff can multiply and release toxins. Not everyone who takes antibiotics gets this problem, though.
Can it come back after treatment?
Yes, it can. Some people have the infection return days to weeks after finishing treatment, sometimes more than once. Doctors have several strategies for repeat infections. Patients should tell their doctor if symptoms return.
Sources
- MedlinePlus - C. diff Infections
- Centers for Disease Control and Prevention - About C. diff | C. diff
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.
