Thank you very much for your reply!
My dosage 1 tsp. of Donnatal as needed, no more than 4 tsp. per day. However, this dosage was prescribed by my general physician when I was not in the midst of a flareup. I didn't have a problem with the drug until the fourth time I took it: a few hours after taking it, when its effect was wearing off, I felt like all of my nerve endings were humming and I was going to jump out of my skin (that's the only way I can describe it).
As far as the Lomotil, my doc simply said to take one every time I have watery/loose stools. So during the kind of flareup I'm currently having, I've been taking about two per hour, lol.
I'm just coming off of a Prednisone regime and will discuss other Crohn's meds when I meet with my GI next week. I'm concerned about taking immuno-suppressant drugs like the ones you mentioned since I work at a university...the number of bugs/viruses/cold that circulate through the student body is downright impressive. 
That being said, I'm considering looking for a new job since the stress levels there are definitely not 'helping' my Crohn's; a new position in an environment where I come into contact with far fewer people would also be conducive to taking the appropriate medications.