Hey there fellow Bengaluruean,
Since you began by 'Patient has extreme itching etc....' one concludes that the one who posted this query is not the same as the patient and the question is being asked for another person.
Irrespective of this, it appears a very specific issues dealing with IgE levels and I'm not too certain on a free open forum like this, any "specific" intervention or solution can be suggested.
This requires a Medical College Hospital kind of scenario to tackle as more extensive tests may be required and use of Immunoglobulins etc and experimental off label indication drugs may need to be employed.
Allergy testing also needs to be considered.
Bengaluru has no dearth of such institutions and i hail from one such..St John's Medical College Hospital.
Suggest you approach one nearest you.
Alternatively welcome to consult ONLINE ASAP and will do our best to find you a solution.
Godspeed 🙏
Health Tips
Non sedative antihistamine eg Fexofenadine -180mg can be considered in a double dose &/or one with Monteleukast combination.