Suffering from IBS

I am suffering from IBS from several weeks. I had my urine,stool,kidney liver examination test done but everything is normal.I have consulted the doctor he told to be the case of IBS .I am taking normaxin,rifaximin,loperamide and condition is better than earlier.But still i am facing the problem what should i do? As i am a professional athlete it is affecting my daily routine physically as well as psychologically.