Lymphocytic Colitis: Causes, Diagnosis, and Medication Management

When you have lymphocytic colitis, a type of inflammatory bowel condition where immune cells build up in the colon lining. Also known as microscopic colitis, it doesn’t show up on regular scopes—you need a biopsy to confirm it. This isn’t Crohn’s or ulcerative colitis, but it can be just as frustrating, especially when chronic diarrhea hits without warning. Unlike infections that clear up in days, lymphocytic colitis sticks around for months or years, often mistaken for irritable bowel syndrome. It’s more common in middle-aged and older adults, especially women, and shows up after years of unexplained digestive issues.

What causes it? No single answer, but it’s tied to how your immune system reacts to things in your gut. Some people develop it after taking NSAIDs like ibuprofen or aspirin. Others link it to thyroid disease, celiac disease, or even certain antibiotics. It’s not contagious, and it’s not caused by diet alone—but what you eat can make symptoms worse. Collagenous colitis, a close cousin with a thickened collagen layer in the colon, shares the same symptoms and treatment path. Both fall under the umbrella of microscopic colitis. Doctors rule out infections, celiac disease, and other conditions before landing on lymphocytic colitis. The real clue? Watery diarrhea that doesn’t have blood in it, no fever, and normal blood tests—yet it won’t go away.

Managing it isn’t about curing it—it’s about controlling it. Many patients find relief by ditching caffeine, dairy, and fatty foods. But the real game-changer is medication. Budesonide, a targeted anti-inflammatory steroid with fewer side effects than prednisone is often the first prescription. It works locally in the gut and doesn’t flood your whole body with hormones. For those who can’t take steroids, bismuth subsalicylate, the active ingredient in Pepto-Bismol, has shown surprising results in reducing diarrhea frequency. And if your symptoms flare after starting a new drug? You’re not alone. Some medications—like SSRIs, NSAIDs, or even proton pump inhibitors—can trigger or worsen it. That’s why an annual medication review with your pharmacist, as discussed in other posts, can be a lifesaver.

You won’t find a quick fix, but you can find control. Most people improve significantly with the right combo of diet tweaks and medication. The key is catching it early and avoiding the trap of treating it like IBS. If you’ve had unexplained diarrhea for more than a few weeks, ask your doctor about a colon biopsy. It’s a simple procedure that can end months of guesswork. Below, you’ll find real stories and science-backed advice on managing gut inflammation, avoiding drug triggers, and finding relief without relying on risky long-term meds.