Reflux and scheduled colonoscopy

I have lpr reflux and I feel it is just now getting under control. I no longer have severe throat/sinus problems but some lingering issues that I hope resolve soon with diet. I am scheduled for a endoscope and colonoscopy this Friday. I am fearful that the prep needed for the colonoscopy(prepopik) will trigger the reflux all over again. Anyone had this situation? I would appreciate if you could give your experience. If I thought it would trigger I would cancel the prep and colon test. My doctor wants to do one since it has been 10 years and I agreed even though I am having no problems that I know of.