I am taking the anti-arrythmic Norpace and while it is keeping my afib in check (had 2 episodes December 2012 and it was increased from 100 mg. twice a day to 150 mg.) for the last 9 weeks, it does tend to make me teary and that is unlike me. I notice it more since the increase. Depression is mentioned as a side effect. I am also very lethargic on it, kind of hard to get things done. Right now the alternative for me is afib. I am waiting for a 2nd opinion EP to see if he has some new ideas. Good luck with this.
I'm sorry I don't have 1st hand experience for you. Anxiety/depression are listed as side effects for Flec.
Its an old treatment for afib but I found beta-blockers worked well, its just that I like hill-walking and the two don't go together too well. I'm going to seek a consultation to change meds - perhaps even revert to Beta-blockers. I hope you get sorted too.