Hi, hope someone can help. Will ring GP tomorrow when open. I am on 25mg per night to ease side pain and break cycle of nerve pain. I am half a month into prescription, and my resting heart rate has gone from 52 to into the 80s. My heart feels likes it's constantly racing and I feel ridiculously anxious, and can't stop the feeling. Any thoughts? I just want to come off this stuff....I feel awful. I did start with 10mg and this was ok. It's got worse in the past week and to be honest I'm not sure I can take much more of feeling this way. I think the pain in my side was a better option.