Microscopic Colitis: Understanding Chronic Diarrhea and Why Budesonide Is the Go-To Treatment

Chronic diarrhea that won’t go away-no blood, no fever, no obvious cause-can be one of the most frustrating health issues to live with. For many people, especially women over 50, this isn’t just an inconvenience. It’s a life-altering condition called microscopic colitis. You might have had it for months, even years, without knowing. Colonoscopies look normal. Blood tests come back fine. But your body is screaming for help. The answer isn’t in the big picture-it’s hidden under a microscope.

What Exactly Is Microscopic Colitis?

Microscopic colitis isn’t one disease. It’s two: collagenous colitis and lymphocytic colitis. Both cause the same symptoms: frequent, watery, non-bloody diarrhea-often 5 to 10 times a day. You might also have abdominal cramps, weight loss, or sudden incontinence. Some people wake up at night needing to go. It’s not Crohn’s or ulcerative colitis. There’s no visible damage during a colonoscopy. That’s why it’s called microscopic. The inflammation only shows up when a doctor takes a biopsy and looks at it under a magnifying lens.

In lymphocytic colitis, there’s a buildup of white blood cells inside the colon lining. In collagenous colitis, a thick band of collagen-like scar tissue-forms just beneath the surface. Either way, the colon can’t absorb water properly. That’s why your stool is always loose. The condition hits women harder: about 7 out of 10 patients are female. Most are diagnosed in their 60s. And while it sounds rare, incidence has more than quadrupled since the 1990s, partly because doctors now know to look for it.

Why Diagnosis Takes So Long

The average person waits 11 months before getting the right diagnosis. Why? Because microscopic colitis mimics other things-irritable bowel syndrome, food intolerances, even stress. Many doctors will tell you to cut out dairy, try probiotics, or reduce caffeine. Those might help a little, but they won’t fix the real problem. Without a biopsy, you’re stuck guessing.

That’s why if you’ve had chronic watery diarrhea for more than 3 weeks-especially if you’re over 50-you need to ask for a colonoscopy with multiple biopsies. Not just one or two samples. At least four, taken from different parts of the colon. One missed biopsy can mean a year lost.

Budesonide: The First-Line Treatment That Works

Once diagnosed, the go-to treatment is budesonide. It’s not your grandparent’s steroid. Unlike prednisone, which floods your whole body with hormones and causes weight gain, mood swings, and bone loss, budesonide is designed to work right where it’s needed-in the colon. About 90% of it gets broken down by your liver before it ever reaches your bloodstream. That means you get the anti-inflammatory punch without the side effects.

Studies show that when you take 9 mg of budesonide daily for 6 to 8 weeks, 75 to 85% of people go into remission. That’s not a guess-it’s from multiple randomized trials published in the New England Journal of Medicine and the UEG Journal. For collagenous colitis, the numbers are even better: 84% of patients saw complete symptom relief compared to just 38% on placebo.

Most people start feeling better within 10 to 14 days. One Reddit user wrote: “Went from 10 bathroom trips a day to 2 in under two weeks. I cried when I slept through the night.” That’s not an outlier. In a PatientsLikeMe survey of 247 people, 68% reported major improvement within two weeks.

How It Compares to Other Options

There are other treatments, but none match budesonide’s balance of power and safety.

• Prednisone works about as well-but causes side effects in nearly half of users: high blood sugar, insomnia, muscle weakness. It’s not worth the risk for a condition that’s not life-threatening.
• Mesalamine (a common IBD drug) helps only 40-50% of people. Too inconsistent.
• Bismuth subsalicylate (Pepto-Bismol) gives relief to about a quarter of patients. Useful for short-term help, but not long-term.
• Cholestyramine works well if bile acid malabsorption is part of the problem-about 60-70% respond. Some doctors combine it with budesonide for stubborn cases.
• Biologics like infliximab cost $2,500 per infusion and only help 20-30% of people. Reserved for cases that don’t respond to anything else.

Budesonide isn’t perfect, but it’s the best tool we have right now. It’s recommended as first-line therapy in 90% of European guidelines and 85% of U.S. ones. The European Microscopic Colitis Group gives it the highest rating-GRADE 1A-for good reason.

The Catch: Relapse After Stopping

Here’s the hard truth: budesonide treats the symptoms, but it doesn’t cure the disease. After you stop taking it, about 50 to 75% of people have symptoms return within a year. That’s why many need maintenance therapy.

Doctors often reduce the dose slowly: from 9 mg down to 6 mg, then 3 mg, over several months. Some patients stay on 3 mg daily for years. It’s not ideal, but it’s better than living with constant diarrhea. A 2020 study in the United European Gastroenterology Journal found that 30 to 40% of patients end up on long-term low-dose budesonide to stay symptom-free.

Side effects during treatment are usually mild: insomnia (15%), acne (12%), or mood changes (8%). Rarely, there’s adrenal suppression in elderly patients, which is why doctors check blood pressure, HbA1c, and bone density before and during treatment.

Cost and Accessibility

Generic budesonide became available in the U.S. in 2018. A full 8-week course now costs $150 to $250. The branded version, Entocort EC, still runs $800 to $1,200. That’s a big difference-and why so many patients complain about cost without insurance. On Reddit, 72% of negative reviews mention price as a barrier.

Some patients find relief through combination therapy. One user wrote: “Budesonide plus cholestyramine fixed me after 3 years. I finally feel normal.” If your diarrhea doesn’t improve after 4 weeks, talk to your doctor about adding bile acid sequestrants or testing for malabsorption.

What’s Next? The Future of Treatment

Researchers are looking at better long-term options. In 2023, the FDA gave fast-track status to vedolizumab, a biologic that targets gut-specific inflammation. Early trials show 65% remission in patients who didn’t respond to steroids. That’s promising-but it’s still years away from being widely available.

Another exciting area: personalized medicine. The COLMICS trial is studying whether certain genetic markers (like HLA-DQ2/8) predict who responds best to budesonide. If you carry those genes, you might have a 90% chance of success. That could mean fewer trial-and-error cycles in the future.

For now, budesonide remains the gold standard. It’s safe, effective, and backed by solid science. If you’ve been struggling with chronic diarrhea and no one has checked for microscopic colitis, ask your doctor for a biopsy. Don’t wait. Your quality of life doesn’t have to be this hard.