The other night I took Tylenol PM for the first time. I fell into such a blissful happy sleep it was amazing. And then I woke up in the middle of the night. My limbs were all so numb and felt very, very heavy, but they also felt like I had ants crawling around inside too. It was the most awful feeling. Never again.
The sleep aid is diphenhydramine, known to many as Benadryl. Some react to it oppositely from it's intended use. It is an antihistamine and reduces itching. (That's what I use it for.) A few years ago, after wrist surgery, I took a couple to help me sleep. I was up most of the night itching and scratching.
It's also good for unblocking the sinuses, which is what I use it for (at night - the drowsiness is a side-effect, I use pseudoephedrine in the daytime when necessary).
Pseudoephedrine here is now only available by prescription. It is used to make meth. That is what I used to use. Imagine me, a former chemistry teacher making meth. Bollocks.