bentyl or what?

I have been through CT scan, blood, and stool tests this week and of course they could find nothing. I have IBS-C mostly but for the last two weeks I had IBS-D So I went in for DX. I do not think anyone has gave me an official DX of the irritable bowel so I am looking to help myself if possible. I of course have all the standard things they give us for it, hyoscamine, bentyl, lomitil,. My question is that if I took the bentyl regularly would it help the IBS-C or make it worse? I am on 20 mgs of prozac which in 6 wks has done nothing for it so I am so frustrated. I do have hep c and I know this sometimes goes along with the irritable bowel. I am afraid the bentyl would constipate me worse if it relaxes the bowel. I tried probiotics and it gave me the runs. I do not want to try laxatives everyday. Does anyone have good results with bentyl? Or what?