Can tegretol or klonopin (clonazepam) cause suicidal ideation /just strange thoughts even at low doses?

Klonopin (clonazepam): especially can cause changes in mentation (it is a sedative). Tegretol, a non-habit-forming anti-epileptic is less likely to do this, but it does change brain function. There is not a lot of difference between tegretol doses that are effective and those that cause side effects (sluggish thinking, and many other side effects).