Can my pain management doc talk to my pcp without permission?

[valiumalleyoop]

I was given xanax by a PCP and he knew I take percocet from my Pain Management doctor by the Rx state monitoring database. Im worried he may call my pain doc and that i may lose percocet. Note that I have never abused and use both for legit purposes. Can he legally contact him or vice versa without my consent? Does Hippa permit this? I would think all they could do is contact or send medical records if i signed something?