Everyone has nights where they have too much on their mind and they struggle to fall asleep. After having frequent bouts of these nights, I always would reach for the Nyquil, because even though I didn't have any cold or flu symptoms, it always made me sleepy and tired enough to fall asleep carefree. SO when they came out with Zzzquil, the sleep aid without all the cold medicine, I bought it. It still works like a charm for me. Within about 25 minutes of taking it, I get sleepy. I take it when I know I have an early morning and am not tired enough to sleep yet. I also take it when I am already in bed and restless. Even taking it and knowing I took it makes me tired. I know the active ingredient is only diphenhydramine, which is the active ingredient in Benedryl, which also makes you sleepy. I know this might seem like a waste of money when the active ingredient is only something that is found in other medicines, but it really works for me, just like Nyquil and Benedryl do. I would rather take just this Zzzquil rather than the unnecessary stuff in other medicines that just include the diphenhydramine. I feel no effects of having to rely on the medicine to fall asleep, and I take it probably once a week. I have had no adverse side effects, like grogginess or inability to fully wake up or feel alert in the morning, even when it is early. I'll stick with this product for my sleepless nights! Just wish it would be a little bit more cost effective.