Well...
I've already seem a similar game to this one, though this one is a bit different with the rat and all.
The graphics, aren't that good, the only actual movements are the rat and the dropping pills. The rat doesn't make any sort of walking animation, and just sort of slides around. At least give the rat some sort of movement.
The controls where just plain bad. Sorry, but it's true... The rat moves, yes, but when you press the button quickly, the rat just keeps moving, even if you didn't hold down the button.
The instructions should be given as your playing rather than in a separate section, since no one really will look at a "how to" section of a side scrolling collection game.
The music is a little bit lower quality and is a little icky at times as far as the sound.
Other than those, there really isn't much else to say other than i'm sorry if i have hurted your feelings.