A few months ago I had a 24 hour heart monitor test done - the results came back normal, and I was considerably relieved. Until today. When I remembered that I was on 80mg propranolol Beta Blockers at the time of the test - I'm not now. What if the Beta Blockers actually masked problems on the recording? Is this possible? Don't really want to phone my Dr, I'm just beginning to convince him I'm not paranoid, lol. [:X]