I will chime in with my personal experience. On my first cruise (a 4 night Bahamas cruise), I took dramamine non-drowsy every day...knowing ahead of time that I tend to get motion sick...and I didn't want to be sick on the cruise. I was MISERABLE the whole time...not with motion-sickness, but just generally feeling "off". I did NOT enjoy that cruise. I just didn't feel like myself. I even told my hubby and the others we were with that when i tell them, somewhere down the road, "Oh, it wasn't THAT bad...we can go on another cruise..." I want them to remind me how I felt on that cruise.
So two years later (LOL) last December...hubby and i went on another cruise (6-night Western Caribbean) ONLY after I did some research...I read somewhere that taking the non-drowsy dramamine might have been the whole problem. So, on our second cruise I didn't take it each day. I just went and packed some to take with me "just in case". The only time I ended up feeling sick was after an excursion day in port where we rode a charter bus all day. That evening, back on the ship, I was a bit sea sick...So, i took dramamine and was perfectly fine the next morning.
We're cruising again 12/6-12/10...Let's see how this goes.