CDI Symptoms: What to Watch For and When to Act

When you develop Clostridioides difficile infection, a bacterial infection that attacks the colon, often after antibiotic use. It's also known as C. diff, and it doesn’t just cause mild stomach upset—it can spiral into life-threatening inflammation. The most common sign is watery diarrhea three or more times a day for two or more days. But that’s only the start. Many people ignore it, thinking it’s just food poisoning or a bad reaction to antibiotics. But if you’ve been on antibiotics recently—especially clindamycin, amoxicillin, or ciprofloxacin—this isn’t something to wait out.

Alongside diarrhea, watch for abdominal pain, cramping that feels deeper than normal gas or bloating, often constant and worsening. You might also feel feverish, lose your appetite, or notice nausea. In severe cases, your stool can turn bloody or contain mucus. Dehydration kicks in fast: dry mouth, dizziness, less urine. If you’re over 65, have a weak immune system, or are in a hospital or nursing home, your risk jumps. Fever, even a low-grade one above 100.4°F, is a red flag that the infection is spreading. These aren’t random symptoms—they’re the body’s alarm system telling you the colon lining is being damaged by toxins from the bacteria.

What makes CDI tricky is how easily it’s mistaken. You might think it’s a stomach bug, a side effect of your new meds, or even stress. But if your diarrhea started after antibiotics, or if you’ve been in a healthcare setting, it’s CDI until proven otherwise. And waiting too long can lead to complications like toxic megacolon or sepsis. The good news? It’s treatable—but only if caught early. You’ll need a stool test to confirm it, and treatment usually means stopping the triggering antibiotic and starting a targeted one like vancomycin or fidaxomicin. This isn’t about guessing. It’s about recognizing the pattern: antibiotics + diarrhea + fever = act fast.

Below, you’ll find real-world guides that break down how CDI develops, how it’s diagnosed, what treatments actually work, and how to prevent it from coming back. These aren’t generic overviews—they’re practical, evidence-based deep dives from people who’ve been there, whether as patients, caregivers, or clinicians. You’ll learn how to spot the warning signs before they turn critical, how to talk to your doctor about testing, and what to do if symptoms return after treatment. This is the kind of info that doesn’t just inform—it can save time, trips to the ER, and even your life.