Absolutely NOT!!!! Vet ***FIRST***. What you are talking about truly sounds like a deep infection -- could be bacterial. Rule that out **FIRST** -- then play with food.
Dog *food* allergies do exist -- however, very very frequently atopy is the primary thing. When did he switch foods? So very often you really can't tell what changed outside, how dry the air got inside, etc.
Picture a bucket under a drippy faucet. The bucket also has a small hole in it. However **sometimes** the drippy faucet runs just a tiny bit faster than the hole lets water out -- EVENTUALLY the bucket will fill.
But there is also rain going in that bucket -- and sometimes the faucet is actually turned ON deliberately and that might fill up the bucket. sooooo -which water is which? The drippy water? rain? leakage from the hose?
does it MATTER? no -- because it's all water.
When it all finally gets to the top and spills over -- what's at fault? The little drips? the rain? the hose?
You can even dump some of the water out. OR you can maybe buy a new hose and stop SOME of it -- but the bucket is still going to be nearly full most of the time --
In other words -- my analogy means the ***allergies*** are there all the time. Now it might be the food that is the EASY thing to "change" -- but are you really getting "rid" of allergies? no -- you're merely attacking one easier potential allergy source -- but most of the time dog allergies hover right near the surface threatening to "run over" most of the time
Dog allergies are similar -- 'allergies' cause things like inflammation in the ears, sometimes hotspots, sometimes sniffles, sometimes major reactions -- but very often it's a conglomeration of MANY things.
To break it down you can get statistics that say about anything -- like some percentage of dog allergies are atopy (and it's really the far far biggest percentage -- like way way over 50 - 65% -- food allergies (real true "allergies" -- as opposed to intolerances) are maybe 25% -- then you have incidentals like contact allergies and flea allergies.
What happens is people tend to hop from food to food to food -- chasing the eternal novel protein. OOPS -- because every single time you switch food, you literally SUDDENLY introduce this enormous whole big new bunch of ***ALLERGENS*** into the body.
new preservatives, new protein, new fibers, new ingredients --
And honestly? You can literally **create** new allergies where there weren't any before.
RAther than just swtiching to a NEW food -- go back to the old one. Be a bit scientific about this. Even if it's a BAD food -- switch back to what was last well tolerated.
Why? Because if, then the problem goes away then it's likely the TOTW. However -- you've got a darned good chance that it won't go away. Because there's a darned good chance that altho maybe the TOTW **helped** by exposing the body to a whole new slew of potential allergens, things like dust/wallpaper mites/dry air from the furnace (full of dust), even the in/out of Christmas decorations or housecleaning or whatever dry/neated air thing you have going on at your house is like in January/February -- that's likely more at the root of the cause of the problem than JUST food.
Now -- at the same time -- better food, with good Omega 3 fatty acids, and good quality ingredients -- those things should make for a healthier dog. But unless you can seal the dog in a room, make it stop breathing, and contacting the floor and outside, it's really pretty impossible to KNOW for sure if "food" is a problem.
NOW -- I hear your frustations about the vet -- but again, approach it **scientifically**.
don't just let the vet hand you another "tube" of stuff. Go in and ***ASK*** for a "culture and sensitivity" -- specifically ask FOR that.
The vet will take a swab culture from deep in the ear. THAT is then sent to a lab. They will identify it (yeast, bacteria, etc.) AND they will also then culture whatever they find and grow 5-6 specimens of it and then apply several different antibiotics to that and see which kills it MOST effectively. They will literally give you a list of 5-6 anbiotics/anti-fungals (whatever "kills" whatever they got from his ears) in a numbered list so you know what's the least nasty drug that will kill it, what won't work at all, and what to use if the first one doesn't clear it up.
BUT you will get yourself a baseline. If the ears are historically fubared, then there's a darned good chance that under it all there IS bacteria. THAT can be continually keeping his ears sore and ripe for problems to set into them.
Allergies can and will add to that. BUT approach it from a sensible perspective so you can truly control it all.
IF it's not bacterial at all -- you may want to try the Blue Power Ear solution (plain alcohol will wipe off the purple) -- and it can relieve the deep symptoms FAST while you attack it from a food/other idea thing ONCE you know, beyond a shadow of a doubt, that you don't have a bacterial infection raging in there.
Bacterial infections don't "show". They don't cause external redness. There may be some head-shaking. Or there may simply be this eternal "ear probllem" that NEVER gets rectified.
A vet who just hands you tube after tube of 'stuff' is dangerous. That's how my Muffin the Intrepid lost his ears. Because ears that are DEEPLY inflamed (but often don't show it externally) will literally harden and the ear canals themselves will ossify. That's rarely reversible. We ultimately had to have his ears removed -- and I NEVER KNEW there was a difference between bacterial and fungal infections, I never knew he had a bacterial one that just never *ever* went away no matter what the vet had done.
Hope this makes sense. Once you get this test done (and DON"T let the vet say "ok I can just look at it in the back" -- NO ***insist*** on the culture and sensitivity - then you have a baseline for whatever is definitively wrong!!!) then you can change food if you feel it's warranted. But -- you honestly would be better off dong a real elmination diet than just bouncing from food to food. But that's a whole other topic.