My dog is 7 months old, she's pretty large, and is still biting...
My dog sometimes gets energized, starts biting her toys, running around the house, and this can quickly turn to biting us and our clothing, specially my girlfriend. Saying ouch in a high pitched voice and ignoring her used to work a bit, but no longer, again, specially with my girlfriend. At this point, she starts biting her clothing and pulling (already ruined a few shirts), and biting the legs and ankles, and not very gently. She also gets frustrated when we ignore her and starts howling and barking so that we give her attention.
We can't continue to ignore her because her bites are painful, my girlfriend is full of bruises due to these bites and she's getting pretty desparate... We had a trainer that I didn't like his methods so switched to another marker trainer, and she's doing really good with all the obedience training - eye contact, ignoring food, etc, but none of this is helping our most urgent problem of biting... I'm looking anywhere I can to get help, it's getting unbearable. Did I mention she's a large dog? (Golden Retriever hybrid)
I should mention that she hasn't been teething for over a month, and that biting us is almost always accompanied by general energy surge. This can happen even after she spent an hour and a half running and playing with other dogs in the dog park, so releasing energy is not the issue. We also try to channel her biting to her toys by playing fetch, tug, etc, but when she's in this biting mood she doesn't care about the toys, only biting us. The only solution we have is putting a door between us, which she then scratches like crazy, barks, and already peeled part of the paint off...