My daughter has had diarrhea for five weeks non stop

Patient: My daughter has had diarrhea for five weeks non stop now. She has use immodium, antibiotics, lomital, IBS treatment and Questran. The study of a monster did not show any virus or infection.She is affected in her work environment and social life. She is really becoming weak and is even becoming emotional over this.PLEASE HELP!!!!

Symptoms: Diarrhea

Doctor: