Sores on head

Hi, my cat Louis started getting sores on his head about 3 weeks ago. They started small and just looked like grazes and I just assumed he was getting into a few fights. Then he got one on his cheek which he wouldn't leave alone and it wasn't healing so I took him to the vets on the 18th. The vet thought that it was an allergic reaction to fleas, gave him antibiotics, pain killers and a e-collar and told me to treat him and the house for fleas. I took the e-collar off yesterday because the sore had healed and within 30 mins he had given himself 3 new, albeit very small, sores. I spoke to my vet today and she's now saying it might be a food allergy.

Has anyone experienced anything like this before?
Also, can a cat spontaneously develop an allergy? We moved house in December, before then we leaved in a house with a field at the back of the garden. There were lots of cats, hedgehogs,  foxes and a chicken coop joined directly onto our back fence. Basically it was fleas galore and Louis absolutely did not have a flea allergy then. 

I've treated him for fleas (Stronghold) and am just waiting for the Indorex I ordered to arrive so I can treat the house. I have however changed all bed sheets and we have entirely wood flooring so carpets aren't a problem.
 

It could definitely be food allergy.  For some reason, food allergies usually present themselves by itching on the head area, strange as it sounds.

What are you feeding him?  Have you recently changed his food, or are you aware of the manufacturer changing anything with his food? In cats, the most common offenders are chicken, seafood, beef, corn, soy, dairy products and wheat gluten.  Did your Vet make any recommendations as to what to do?  If he suspects food allergies, then you may need to figure out what he's allergic to and obviously eliminate that from his diet...not an easy task .

Now, there is another option that this could be, and that is contact dermatis, since you have recently moved.  That is kind of suspicious to me.  It's possible he is rubbing his head and cheeks against something that he's allergic to.  Again, you will have to put on your detective's hat to try to figure out what that might be. 

In the meantime, if you could give him a supplement with Omega-3 Fatty Acids (like Salmon Oil or Krill Oil), that may help him, no matter what type of allergies he has. 

Here is an article concerning allergies and skin problems in cats which you may find helpful:  http://www.thecatsite.com/a/allergies-and-skin-problems-in-cats-cause-and-natural-treatment

that you can get to the bottom of this issue

He eats a mix of wet and dry, though brands tend to change a bit depending on where I'm shopping. He did have a new food which he'd never tried before about a month ago so it could be that? Thanks for all the info and the link, I'll have to do a bit of detective work then!

If anyone has any suggestions to help with the itchiness whilst I'm working it out, it would be appreciated!!

Im thinking along the same lines as MrsGreenJeans... One reason why allergies are often visible on the head is also, the fur there is thinner, possibly also the skin is thinner.  And thus, sores and skin defects become visible for the naked eye...

One question: Is Luis neutered?  Our older resident had some allergic problems, mainly with fish. Everything disapeared  after he got neutered (he was a stud in to almost 3 years)... If it was partly hormonal, or partly stress,I dont know, but nowadays he can eat fish and tuna, and has no allergic problems at all...

The tricky with testing of foods (and litter), is it not always goes better immediately you change. Sometimes it takes several weeks...So the trial and error may take its time and effort.

"chicken, seafood, beef, corn, soy, dairy products and wheat gluten."

A comment here: I dont think chicken as such is very allergic. But chicken is very common in many cat foods, and thus, gets allergic statistics against itself...  The others are often mentioned as main suspect in allergies yes.

So one way is to try with safe alternatives. Turkey, lamb, vernisome are often mentioned.  If you can find James Wellbelowed dry food, it is often used here.

Most wet foods dont contain these cereals and soys... So if you cat eats wet...

Goat milk is much safer than cow milk - and its products...

Goat milk is also useful as a bas for an alternative feeding...  As he can survive living on goat milk.

Last but not least. I had understand the vets have nowadays tests for some allergic reactions. They were barely coming when our boy was a man with allergies.  But they had come since...

Good luck!

My vet suggested Hills hypo-allergenic food (I'm UK, not sure if Hill's is sold anywhere else), which is venison based, so I think I'm going to try that for now and then maybe slowly reintroduce food that I know he's always been okay with. 
Yes he is neutered, we have just moved house though and as Louis is already a very nervous cat, it was very stressful for him. I'm hoping the stress is what has caused it and he will rebuild his food tolerance if that's what the problem is! My vet did mentions tests but also said they can cost up to £400!! So I'm going to try the hypo-allergenic food first and see how it goes. Thanks for the information!