Tight foreskin hard to pull over penis head.

hi,

I have a tight foreskin, which is hard to pull over the head of my penis when erect and flaccid. I read that there is a cream I can get with a doctors prescription that will help loosen the skin combined with stretching. I had a couple of questions. Can I get a prescription for this from my local gp, or do I have to see a urologist? And also, will I have to use the cream constantly for the rest of my life (as I've read it wears off after a while) or do I just use it until I can fully retract my penis?

thanks