Wow, some odd info here. Klonopin is very often used for long-term, and is quite safe as long as you do not abruptly stop taking it. There is no evidence it causes brain cell death at all, but it can interfere with memory while you are on it. Usually at low doses this is pretty minimal. Of all the benzodiazepines I use this one the most as it is very long-acting, has some anti-depression qualities, and works very well to prevent anxiety states.