The Goji Juice being marketed right now also contains grape juice. Grapes & it's juice can kill your dog. No one knows why it happens since it only happens VERY infrequently. Yes, I know, you've given grapes to you dog in the past and nothing happened. I have too. Odds are it won't hurt the dog at all, but every once in a while it can kill him/her.

If you have doubts, then do an internet search to verify it.
The Goji part of the juice may be good for the dog, but don't take the risk unless your dog is gravely ill and this may be it's last chance.