german shepherd ears

Question
My German shepherds ears are red and itchy there is no odor no dirt or debris that I can see.  He has been scratching them and now I'm seeing a little blood and scabbing. He doesn't seem to cry yelp or whine and he let's me mess around in there but this morning he kinda grunted when he was itching.  I got him from a rescue group about 3 months ago and he had red ears then too but the lady gave me a cream to put on them and it worked pretty good but I can't remember what it was called.  About a month ago we took him to vet about skin being pink and scratching nonstop and whining she said seems allergic to fleas gave him shot and antibiotics and within 2 hours of shot he was a brand new dog and also with that shot his ears cleared up completely.  Could being allergic to fleas affect his ears I haven't seen any fleas around outside inside or on either of my dogs I'm also wondering if prednisone would help although that wouldn't cure him. What are your suggestions thank u  

Answer
If he resp0onded to the shot, then he has allergic ears.  Rarely is it a flea allergy, that usually affects the lower back, but apollen, mold, type of allergy.  Yes, low dose, every other day prednisone is perfectly acceptable to control the symptoms of allergies.