Is it possible for someone who as had a dog for 14 years a Dalmatian X Labrador all of a sudden becomes allergic to a 7 month old Labrador puppy that they have had for less than 24 hours?

i would say yes definately, allergies can strike from no where and labs are very hairy and lose a lot of fur. i would bath pup to get rid of any previous smells and maybe use petal clense on the coat which is meant to cut down on the allergy. you may just need time to adjust to the new smell of the puppy- take some piriton too and give it a while to settle.

Should have said it was my pup that was sold to someone with the 14 year old dog she was to be train has a dog for the disabled.

I should think the dogs would have fur of the same type as I had one of these cross's years ago but mind was more lab than Dalmation.

The person did try piriton but it did not work for them I did use a coat conditioner with (evening primrose) on her before she went and thought this could have been the problem for the allergy?.

My husband is like this when ever we have a new puppy :)

It normally take a few weeks for him to de-sensitise :)

Same here, starts with 'no we are not having another one' and ends up with the little rascal sitting on his lap as if it has always been there.

I react to some dogs and not others.  And my allergies have always flared a bit with the addition of a dog to the house but settles down over a week or so.

I'd say Yes, only because I used to be allergic to dogs until my mid 40's then it suddenly disappeared and I'm ok now so we have a dog.  I've got a golden retriever and don't have a problem at all with this particular breed.  However, we do have a friend with a lab and I sometimes get an allergic reaction to that particular dog and I find that I can smell him immediatley as soon as he walks into the room, which is sad as he is a lovely dog and I can't get close to him!