Been lurking on this thread since it was posted and doing a little research myself, since I've always been told it's toxic or semi toxic and I'd hate to be spreading misinformation. Here's what I've been able to dig up:
"Avian Pain Management - Joanna Paul Murphy, DVM"
Text of interest:
Quote: "Controlling Avian Pain - Karen L. Machin, DVM"
Text of interest:
Quote: Based on this and other reading I've done, my takeaway is that medications in the "-caine" class CAN be used, but use and amounts should limited as they do appear to have the potential to be toxic.