Doxepin
"I have been taking 25 mg of Doxepin for 17 years, I always could fall asleep, but if I woke up during the night, I couldn't go back to sleep for hours. Doxepin was like a miracle to me, I was never groggy the next morning and it didn't make me sleepy and groggy right after taking it.  It just lets me go right back to sleep if I get up to use the bathroom.  It still works after all these years, not as well though.  I have weaned myself off of it, but I start having hot flashes off and on all day...so I start taking it again.  And after being off of it for a few days the sleep problems seem to be back...so I may be on this for the rest of my life. I have recommended this to several friends and it has also helped them."