I switched from Diovan to Clonidine Patch about a month ago and have had some major irregularites, am now wearing a holtor monitor. I have had some heart palpatations in the past while on other meds but they now last up to 16 hours at a time. The rhythum is not fast, just very disorganized. My doctor doesn't seem too concerned. The nurse told me that Clonidine patches do not cause this problem, but when I was not on any meds I never had these irregularities.