| Cause | Features | Treatment |
| Infectious diarrhea | ||
| Viral infection | Loose stool, low-grade fever, feel ill | None, usually resolves within 48 hours |
| Bacterial infection | Fever (temperature >101°F or 38.4°C), bloody stools | Usually none, antibiotics in selected situations |
| Parasite | Not common in developed countries, may be seen in returning traveler or camper | Antibiotics in most cases |
| Non-infectious diarrhea | ||
| Antibiotics | Loose stool begins after antibiotic started, usually resolves with a few days after stopped | Usually none |
| Food intolerance (eg, lactose intolerance) | Diarrhea, abdominal pain, and/or gas after consuming food | Determine if food intolerance is the cause |
| Inflammatory bowel disease (eg, Crohn's disease, ulcerative colitis) | Mouth sores, diarrhea, abdominal pain, weight loss, and fever | See a healthcare provider for full evaluation and treatment |
| Irritable bowel syndrome | Chronic lower abdominal pain, diarrhea and/or constipation | Symptomatic treatment |
| Celiac disease (gluten sensitivity) | None to diarrhea, weight loss, abdominal pain, gas | Complete avoidance of wheat, rye, barley |
