Why only change one thing at a time? Because if you change two or more things at a time you can't know what is causing good things and what is causing side effects. Even though you don't like it, it is the appropriate way to change medications. Give it a little time to see if there are more side effects, call in for another appointment and then have a med change for the stomach/intestinal problems. But, you might temporarily try an over the counter medication like Pepto bismal.