Er, by "nose stud" are we talking of what is commonly known as "nose bones," straight with a ball at the end? I've heard horror stories about piercings closing to the size of the bar and the ball no longer fitting through the hole...and the stud having to be cut for removal. It's NOT advised to use them.
I'd also suggest diluting antibacterial soap with water, as it can be too harsh on piercings.
(all of this from bmezine.com)
