Took imodium (loperamide) for a while, but diarrhea has persisted for a week. doctor confirmed it wasn't bacterial. what should i do?

Try probiotc: There can be a lot of causes of diarrhea besides infectious (bacteria or viral). You might try to restore your normal flora in the G-I tract with probiotc like Florastor or Align which you can get OTC; but if that does not help then you may need other tests to look for other causes of diarrhea such as inflammatory bowel disease or gluten sensitivity.