The short answer is that we don't know.  It's possible to go into remission for quite a while.  On the other hand, it's also possible that if you stopped your medication, the RA (and therefore the pain) would flare.  There's simply no way to tell.  Hollybgroovin gave a terrific answer to a similar question here.  If you do want to try going off your medication, make sure you do so in consultation with your doctor - he or she may be able to guide you through it and suggest things you can do to help your body manage better.

Good luck!

Of course there is never any way to tell for sure.  The problem is that if you no longer have pain, there is a good chance that is because you are currently on medication.  Please keep in mind that while it is possible to be in remission, RA is still an incurable disease.  It is also a disease that can cause significant damage even when no pain is present.  While everyone is different, RA has been known to come back with a vengence when treatment is discontinued.  That is why most rheumatologists will tell you that treatment for RA is a life-long battle.  I would speak to your rheumatologist.  He should be able to voice his concerns about discontinuing treatment and give you a better understanding of what it might mean in your situation.  Good luck and best wishes!