Medically reviewed by Anju Goel, MD Key Takeaways Diarrhea is often contagious, especially when it's caused by viruses, bacteria, or parasites. Infectious diarrhea can spread by not washing hands ...

Diarrhea usually resolves in a couple of days, but it can sometimes continue for weeks. Persistent diarrhea can be a sign of an allergy or a chronic condition, such as inflammatory bowel disease (IBD) ...