Hi, Persistent and severe bouts of diarrhea can have various causes. Some possible causes include: * Infection: Bacterial, viral, or parasitic infections can cause diarrhea. These infections are usually acquired from contaminated food, water, or contact with an infected person. * Food intolerance: Certain foods can cause diarrhea, especially if you have an intolerance or allergy to them. Common culprits include lactose (found in dairy products), fructose (found in fruits and some sweeteners), and gluten (found in wheat, barley, and rye). * Medications: Some medications, including antibiotics and chemotherapy drugs, can cause diarrhea as a side effect. * Inflammatory bowel disease (IBD): This is a chronic condition that causes inflammation of the digestive tract. Symptoms include diarrhea, abdominal pain, and rectal bleeding. * Irritable bowel syndrome (IBS): This is a common condition that affects the large intestine. Symptoms include abdominal pain, bloating, and changes in bowel habits (including diarrhea). * Anxiety and stress: Emotional stress can cause diarrhea by affecting the normal functioning of the digestive system. * Other medical conditions: Certain medical conditions, such as thyroid disorders, diabetes, and pancreatic insufficiency, can cause chronic diarrhea. To determine the underlying cause of your persistent and severe bouts of diarrhea, it is important to consult a healthcare provider. They may perform tests such as stool analysis, blood tests, or colonoscopy to identify the cause of your symptoms. Treatment will depend on the underlying cause and may involve medications, dietary changes, or lifestyle modifications. In some cases, surgery may be necessary. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Priyanka, General & Family Physician