How to help dog with severe food allergies?

the problem with severe food allergies is you will just be managing symptoms for the life of the dog ... i do not suggest allergy testing or immunotherapy (allergy shots) because that is very expensive, not definitive, and the shots in no way are a cure, and sometimes useless ... i spent thousands on allergy testing and shots with a doggie allergist all for nothing ... do you have the dog on any medication like antihistamines or prednisone ??? my dog lived the majority of her life on both of those ... the raw diet and science diet zd were absolutely the worst ... i have her on a limited ingredient grain free diet and for the first time in 10 years she is off all allergy medication ... but it is hard because she can not have one single bite of anything else or her allergies are triggered ... allergies are a challenge to deal with both in dogs and people ... and many people live their lives with "head colds" due to allergies and sadly some dogs have to live equally uncomfortable ... i would suggest a limited ingredient diet with no grains and nothing else for at least four months to see if there is any improvement ... and use a protein source that is unique to the dog, something the dog has not had before ... the reality is many vets do not know much about dealing with allergies ... i went to one vet to ask about atopica (another thing to consider, worked wonders in my dog, just very expensive pill to take) and he googled it with me in the room !!! my dog has been on every diet under the sun (nutro, california natural, orijen, taste of the wild, raw, evo, barf, kangaroo kibble, vegetarian kibble, science diet)and the only thing that has helped is this new limited ingredient diet .... there are several companies that make these diets, the one i am using is nature's balance sweet potato and salmon ... it comes in canned, kibble and treats ... good luck because i know how challenging it is to deal with allergies and to see your dog so uncomfortable ... one last piece of advice, do not let any vet talk you into a cortisone shot ... it is painful for the dog to receive and is of very minimal benefit ...