I do it for the exact same reason as the other Tara said - it works for us. I've tried Tylenol PM & it had zero effect. Whatever the sleep aid ingredient is in that, it doesn't work for me. I've been using Benadryl off & on as a sleep aid for 20 years & it works. Plain & simple. It's the only thing I've tried that knocks me out but whe I wake up, I'm not a zombie. I couldn't care less that I'm putting the other OTC meds from Benadryl in my system, if it works in my body to make me sleep, then that's what I use it for. I don't "hope" to get the side effect of sleeping like you stated, I DO get that side effect, every time. It might not work for others, but it works best for me.