That's right - it suppresses activation of microglial cells, which form the brain's immune system. Drugs.com has NO information about this.
I had an ablation for a-flutter in April 2014, and a second one for PAF in May 2015. After the second ablation I was prescribed flecainide 100mg 2x/day. It gave me some nasty side effects - primarily dizziness and fatigue - that got worse after I stopped taking it after five weeks. A few days later the symptoms increased to the point of disability.
Because the dizziness and extreme fatigue keep me from driving or doing much work, I have been home-bound for most of the 5-1/2 months since May. I can't do most of the things I've enjoyed in the past - canoeing (I'm an instructor), camping, road biking, classical guitar lessons, dating, or visiting my grandson 90 miles away.
I believe this is what happened: I had a pre-existing infectious agent in the brain (possibly Lyme disease but tested negative) that the microglia were keeping in check. When they were suppressed, it came out and did damage. When the microglia re-activated they beat back the infection but also attacked the damaged neurons, sensing the damage as foreign - as happens in multiple sclerosis. My neurologist agrees that this is a reasonable theory.
When I told my cardiologist about flecainide's immunosuppressant effect, he did not appear to have ever heard about it. He prescribes flecainide routinely but did not know.
How could the cardiologist not know?
How can drugs.com - and a bunch of other medication-related websites - not list such an important effect?
WHAT IS WRONG WITH THE MEDICAL COMMUNITY?
I now have what is likely to be a lifelong central nervous system problem. Good thing I'm 66; I have only about 20 years of disability to look forward to.
Thank you, drugs.com, et al., for ignoring the life-destroying effects of a common medication.