My dog seems to have become alergic the the sandfly collar. She wore one last year with no problems, but this year seems to be constantly scratching at her neck when wearing it. I have had to remove it as she was making her skin raw, left it a couple of weeks and tried to reintroduce it by just leaving it on during the day and taking it off at night. She started scratching at her neck again after a few days. She has had the sandfly course of injections as well but the vet advised me to still use the collar, she assured me that they were two very different chemicals and it would be safe to wear. Has anyone else had their dog react to the collars? I am mostly concerned about when we get to Portugal as the sandfly problem is supposed to be worse there.