Hello and welcome. Rifaximin is a semi-synthetic antibiotic and may hardly do yiu any good with your current symptoms. You need to firdt get diagnosed, you have not mentioned any fever and so you will require a blood analysis, stool analysis and a more elaborate history. If at all an infection is diagnosed ofloxacin would be more suitable. If conditions like gastritis, peptic ukcer disease, etc; are diagnosed then their specific treatment regimens will have to be initiatwd. But if a chronic condition like irritable bowel syndrome, diverticulosis, etc; are found from a colonoscopy then their respective treatment regimens will be required. Best wishes.