The tylenol PM is just tylenol with "benadryl." Gotta be careful not to take too much tylenol, it's murder on the liver.
I found that taking 1-2 "generic benadryl" helps me fall asleep. My GP also gave me some ambien CR which definitely helped though I don't like taking it.
Here's the funny thing: Some nights just knowing it's there seems to help me sleep. Without it sometimes I'd get so afraid I would not be able to sleep that I had trouble sleeping. Now that I know it's in the drawer if I need it, I don't worry about it and thus usually can sleep without it. Once in a while, if I still can't sleep, I'll take the pill.
Part of my problem was the pain meds - I have a "paradoxical reaction" to some stuff, and the oxycodone for example gives me insomnia. This was a lot of my problem before my TKA. I couldn't sleep for the pain, and if I took enough meds to kill the pain I couldn't sleep for the meds. I was too hard-headed then to take a sleeping pill -- "I don't want to turn into a pill-head."
In hindsight, that was stupid of me. I still don't want to take lots of pills, but darn it, if I need it I am not going to suffer for no good reason. If I need a good night's sleep, that's what the pill is for.
HTH...
DD