
Hi Tina
Having a dog that loves to 'hunt' for birds, rabbits, squirrels, moths and flies I do sympathise.
I do not let my dogs off lead unless I am in a secure area and even then I have to keep my eye on Henry as he goes off in a bit of dream, chasing anything and everything and having 'cloth ears'. He is generally worse in the spring but this time it seems to be going on. I'm not sure the hunting instinct gets worse as they get older, Henry is 4 and a collie/retriever cross, but I do think if they are the type to hunt it is difficult to stop them, as my other dog a golden retriever isn't the least bit interested in hunting, well occasionally but he is not obsessed as Henry is.
My advice would be to continue as you are with recall but don't let her off lead unless it is completley safe to do so, I personally wouldn't want to sedate her for doing something that comes natural to her.
Good luck, hopefully you will get more advice from the experts soon.