Imipramine
"Taking at a very low dose to help me sleep as I have fibromyalgia related to arthritis.  I tried two other drugs before this one and both have me extremely bad nightmares.  I have found that I don't get nightmares with this one.  Within an hour of taking, I am solid asleep virtually all night.  I don't get foggy the next day.  I really haven't had any side effects except for a slightly dry mouth, but I am on 10mg."