I recently seen a dr for white patches in my mouth and was told it was my seasonal allergies that are causing the white patches is this true allergies can cause white patches in mouth? and i also have been sneezing?

Yes, that can be: There are many causes of white patches in the mouth, some of which are painful and some are not. Allergies can cause this. Without seeing them, it is hard to be sure. If you have allergies, allergy medicine may help; sometimes they are from dry mouth, so then drinking plenty of fluids may help. Please follow-up with your doctor if they are painful or not resolving with those therapies.