I haven't seen these two discussed as being used together, so I thought I'd offer my experiences:I have the "D" type of IBS. I've been using Levsin symptomatically for a number of years with limited success - my biggest complaint about it is how dehydrated it makes me (I sing, and when I've taken Levsin, I've had my throat slam shut mid-note in front of an audience - not fun!).Early this year I had ongoing abdominal pain that wasn't responding to ANYTHING. I was also seeing a new doctor, and she suggested we give Buspar a try since it was supposed to have some effects on IBS (she said it wasn't a very effective anti-anxiety medication, but that it was actually showing more usefulness for IBS).It seemed to work for a while - my BM's seemed to get more formed and less frequent, and I was optimistic. Then I had a MAJOR attack (while out of town, of course!) and in the following days just couldn't seem to get back to normal.Well, this was right around the time that the Lotronex became available, so I called my doctor and told her I was game to try it, and she sent me home with some. At the same time we also stopped the Buspar.I saw a difference almost immediately. Basically, I quit having BM's (something a lttle unsettling when you're accustomed to having 6-8 per day!). But the ones I had seemed firmer, and so I kept taking the Lotronex.Well, in about the third week of the Lotronex, I suddenly developed some VERY severe cramping that was frightening (and disabling) in its intensity. I called the doctor's office - it took them two days to get back to me - and I began taking Citrucel since I wasn't having BM's and I felt like I must have been all blocked up. About the time the doctor's office called me back, I began having tiny little rocklike BM's, and while still in pain, it was more intermittent.The doctor felt that my body was still going through an adjustment period and thought the Citrucel was a good idea and asked me to give it a few more days and then come in to see her, which I made an appointment to do. In the meantime, I had to cancel another out of town trip which I had been looking forward to.By the time of our appointment, I was still having intermittent cramps. It was my thought that when I had fecal material in my gut (that hard, rocky stuff that I'd been having since going onto the Lotronex) that its simple presence there was painful and causing me cramping (I don't know what it feels like for other people when they need to have a bowel movement, but for me it ALWAYS hurts - whether it's D or C).She was doubtful, but I told her I'd read a few references that said that IBS patients had more pain receptors in their gut, and that I really felt that was what was happening. It just plain hurt when I had sh** waiting to get out!So she suggested we go back to the Buspar ALONG WITH the Lotronex. She felt that Buspar's anti-anxiety properties might help with my body's tendency to get the crampy gut, and that it was a pretty low-risk med to try. So - even though I HATE being a walking medicine cabinet, I agreed to give the combination a shot.Well, it's been almost three months now. I'm taking Lotronex and Buspar morning and night, and Citrucel in the morning. I haven't had what I would term an "attack" since being on this, although I have had instances of painful gut (and honestly, I don't believe I will ever be free of those). I even just got through two weekends of playing Marian the Librarian in a community theatre production of "The Music Man" without any major attacks during the run of the show!My stools are mostly pretty well formed - sometimes they get more "rocky", but I think the Citrucel helps a lot with that. And I'm also being really religious about drinking eight 8-ounce glasses of water per day. (I measured 8 ounces, and it was a lot less than I thought it was!).I saw the recent notice about Lotronex, and I'm a bit concerned. Could it be that the adverse effects all came from C patients that should have never been given Lotronex in the first place? Because I couldn't *imagine* having STARTED out with C and then going through what I did! I think that would have KILLED me!Well, sorry this was so long. But I haven't seen any other discussion of this particular combination of meds, and I thought it might be helpful. Seems to be working for me!