Is it possible to be allergic to formula but not to cow's milk?

[Char11]

Hi,
I have a 10 month old DS who has been almost exclusively breastfed. When he was very little we queried lactose intolerance /cmpi as he was very colicky and DH is lactose intolerant. Tests came back negative.
When we started weaning, we very slowly introduced dairy and he has seemed fine with it - eats cheese, yoghurt and has cow's milk on cereal.

About a week ago we decided to start weaning from daytime breastfeeds and began giving a bottle of formula in the day and one at about 10/11 pm when he wakes (he is, and always has been a terrible sleeper, still wakes loads!!!).
Anyway, he has developed a rash on his forehead and cheeks which seems to be spreading. He has been very gassy, slightly off his food and has cold symptoms too. It occurred to me today that it could be a mild allergic reaction to something, and the formula is the only new thing in his diet.
But, could he be allergic to formula even if he doesn't seem to be allergic to cow's milk?

Any ideas would be really great :)

There's soya in formula milk, could it be that? DS never got on with formula, we went straight to cows milk at around 11 months. I think it was probably a soya intolerance.

Look at the ingredient list. Formula contains all kinds of things in addition to milk. eg some have fish extracts. It's perfectly possible to be allergic to one of the ingredients.

Could you consider continuing to breastfeed?

I can do for a while, but go back to work in August so was hoping to dramatically reduce by then. Although he will be 1 in July so maybe it's better to just skip the formula. I've stopped giving it for now and will see if the rash etc clear up. I guess it would just be nice to know if it is an allergy and if so, to which ingredient. Can the dr test for all the various possibilities? Can't imagine he'll be that keen!

He eats fish, and seems ok with that, but could be soya I guess. Thanks for the tips,

I have been told by my DM that I could not take formula, she did not breast feed - so she gave me cows milk from day 1. And I was 3 weeks prem (which was quite a lot all those years ago!).
I'm here, very healthy with 3 big strong healthy boys ....
Don't beat yourself up about it, I gave mine cows milk from about 9 months, also, just a thought, try goats milk if you think there are some allergy issues.....

Yes, DD1 couldn't tolerate formula but went happily onto cows milk at 12 months and had been eating cheese, yoghurts etc since about 9 months.

I took him to the gp, she said it is just eczema, not an allergy, and just prescribed a cream. It was only afterwards that I thought that surely eczema can be the manifestation of an allergy. So I'm still not convinced really and we have stopped the formula and will see what happens.
I'm actually considering eliminating dairy for a few weeks too, just to see if his sleep improves...

Eczema is a really common manifestation of food allergies and my DD2 gets it from dairy and gluten (I think, we're doing an elimination diet at the moment).

Over the years and with 2 DC's who've had problems with formula and foods, I've realised sometimes, the GP, HV etc aren't entirely reliable. Do it your way, going dairy free sounds like a good idea to try.

That's interesting EMS, they do seem reluctant to entertain the possibility of an allergy. I don't really understand it, as its surely better to look into it, even if its just to rule it out.
Is there a good non-dairy milk to use for his cereals, do you know?

DD1 had Nutramigen up to 1 year, then straight to cows milk.
DD2 was prescribed it too but she couldn't tolerate it so I asked the doctor for Neocate. He was really reluctant and we "discussed" it for a good 10 minutes before he would give me the prescription. He admitted it was as much about budget as anything else. We use 3-4 tins a week and they cost approx £50 a go.
In the end, he relented because it was clear I'd done my research and I am an "experienced mother"! All very well but I don't think I should have had to prove my credentials to get the prescription. And he's the best, most sympathetic GP we've seen about this.

I've not had to use milk substitute as DD1 went straight to cows milk and DD2 is only 8mo so still on Neocate but I've seen Oatly and some coconut milks recommended on here.

I've also noticed Lactofree at the shops and wondered if that would be worth a try in the future if DD2's intolerance persists past 1 year.

Going back to your original message, I note that your LO is fine with processed dairy - cheese, yoghurts etc. These are all easier to digest for the lactose intolerant, as the proteins are broken down to some extent. Although processed, I think the proteins in the formula, would not be broken down to the same extent.

Under 1 year, unless you are able/prepared to express your own milk, you should use a hypoallergenic formula for cereal/main milk drink - on prescription it costs you nothing, but will cost your GPs practice - hence reluctance, I think!

Speaking from experience, should you decide to breastfeed dairy free, you need to take calcium tablets with vitamin D. Tescos own are fine. Also push for referral to a dietitian for you and him.

Ah, thanks for all the great tips and advice. His dad is lactose intolerant, and has been since birth, so that makes sense about the cheese/yoghurt. I haven't expressed for a while but will get the pump back out and try again. Will try some of those alternative milks too, but doubt I'll be able to get it prescribed as they don't seem convinced he needs it, so I guess I'll just stick with bf primarily.

Lots of great ideas, thanks mumsnetters :)