Ear issues can be caused by lots of different things. If you are sure it's allergies, the most common issues are wheat, pork and corn.
But dust, grass, and a 100 other things are also possible. A mild allergy pill, daily ear cleaning and a change in diet will help limit the ear issues but it will not get rid of it completely.
Diet to fix food allergies. Find a wheat, corn and pork free dog food. Takes about three weeks for see results. If this doesn't work, you may have to try a prescription food.
Allergy pills to fix pollen or grass allergies. They can be gotten over the counter at most grocery stores but get your vet to okay them first. Chloraphanarmine (spelling). Little yellow allergy pill. VET OKAY is a must to use this!!!