When I was a little younger, my mother used to buy these for me to help deal with my period. Now that I'm older, I don't experience cramps like I used to, so I stopped taking them. I always personally thought they were a great product for my issues. If I ever have the need to start taking them again, I'd do it in a heartbeat. Effectiveness The only issue I've ever really experienced with my period is cramps. I've never really had to deal with mood swings or the like, so I don't know how well Pamprin will help with those types of things. But for me at least, they always helped get rid of my cramps for a few hours, which is all I ever really needed since they usually only lasted a couple hours to begin with. Immediacy These always worked straight away for me. I had to wait maybe at most a minute or two before I started to feel their effect, and then it lasted for the next few hours. For something like this, I'd consider that pretty immediate.