Any davice on giving up nicorette chewinggum?

I was a heavy smoker from the age of 16. I gave up 9 years ago without any problems, using first lozengers then onto gum bu tnow I am addicted to the gum, i have a piece in my mouth virtually all the time. If I am at work, I don't miss it, but have to have several in succession after work, just like I used to with a cigarette. I have tried normal chewing gum, but I can't bear it and quickly revert back to nicorette. The thought of not having any panics me and it's costing a fortune! Any advice?