When my babies were puppies I gave them a bath once a month, or once every 3 weeks if they're dirty (now, every 2 weeks just because their hair is long). In between, I wash their feet, behind, or rub them down w/pet wipes. Over rinsing is a must, left over residue of shampoo can cause dandruff. I wouldn't add anything to my puppy's food, you might want to wait on that. I use Frontline & it's applied directly on their skin in the back of their neck area, so I don't think it's the cause of dandruff. Mimi & Momo does scratch the area though after I apply, so I hold them until it dries. Afterwards, they're fine, so I don't think that's the reason for itching. But every dog is a little different. Hope your baby girl gets better soon.
