She is currently on frontline and sentinel, so I don’t think it is fleas, can it be an allergy or other mite? Or what?

All of a sudden my dog started scratching nonstop. I knew it wasn’t a flea problem because I put her Advantage every month. I took her a bath and she had a red rash on her front chest and front legs. I took her to the vet and he says it is an allergy. He gave her two injections and said that the scratching would stop immediately. He also gave her some antibiotics and steroids. She did get better but I worry it could be something else, possibly mites?

I took my border collie to the vet because she has a really intense itch on her back and tail. The vet said it is flea allergies, so she gave the dog a pill to get rid of the fleas in 24 hours and some topical Advantage Multi. She is still itching like crazy. How soon will the flea bites (assuming the fleas are gone) stop bothering her?

our 7 year old dog has excessively dry and scabby skin (vet said its not mange) and ear infection (vet said to use vinegar even though he did not do a culture). we are pretty sad and would like to do anything we can to correct it. our vet is kinda maybe too holestic & money hungry for us. lol. we are probably switching vets and switching foods.
so, our doggy would of course love your help. we’ve seen dogfoodanalysis.com
1.) i was always pretty sure that when shopping for dog food, you should always select a type that indicates meat as the 1st ingerdient. so, what is meant by “deboned” meat or meat “meal”??? would that not be as good as just the named meat product instead?
i am trying to pick among conidae, orijen, wellness core, and innova….but some feature deboned and meal as the first ingredients and some feature fresh meat or just the named meat and it’s all pretty confusing. help.
2.) raw diet? could this be better? suggestions? sounds expensive but possibly healthier

My moms great dane has had loose stools recently, has always had a ton of eye “buggers” and red ears (not ear infections but very red and raw looking). I have been telling her to try switching from kibbles n bits to a better quality food and today she switched to Canidae ALS. I know that if these things were food related they would not immediatly correct themselves but what is a reasonable amount of time that if they were food related they should correct themselves?
I personally noticed a reduction in the eye buggers when I changed food last year but is this something food related or could I have just changed when the seasons changed?
Thank you.