Dear Mirna ji
In all such cases the cause of allergy
can be external or internal. You have noticed external causes as allergic to milk products or soya but rule out internal causes where intestinal worms are major factor. Get her stools examined. Increase the immunity of the baby to prevent recurrent attacks with Swamla i tsf bd. to cure hives
Ayurveda offers cure with Haridra khand 250 mg. and tab . gandhak rasayan 1 bd.