Welcome to heathcare Magic!
The problem of esophagus
, the urticaria
and the antihistaminics are not causative by any relationship.
The first two problems are totally unrelated and are by chance together.
The treatment of Chronic Simple Urticaria is Levocetirizine
5 Mg day, it is most effective treatment but needs to be taken for some >3months continuously and you do not need steroids
on it, I would warn against steroids because they can be terrible for esophagus disease.
Rantac 150 twice a day is good enough, take for two months and then let me know.
Wish you a great health!