Thanks for posting on HCM and welcome,
as you are presenting can be as a result of any one of the numerous skin affection and so you will need to exercise a lot of patience with the health care practitioners to determine the cause and provide definitive treatment. Causes for your own skin itching can be local ( due to direct skin affection) or due to an underlying diseases condition. Faced with situations of chronic itching, I will suggest specialist consultation with a dermatologist
If several antihistamines do not work, then it is most probable that the cause is not allergic so we need to start looking elsewhere.
Now given your presentation, I will suggest you get treated for scabies with benzyl peroxide lotion and maybe with a antibiotics combination such as clarithromycin
ectc. Additional steroids
(oral or topical) will be helpful.
Blood tests should definitely be done to exclude any underlying diseases condition.
Microorganisms ranging from bacteria, parasites, fungi, viruses could be responsible and need to be checked.
Your treatment should be multidisciplinary (hygiene and sanitation, medications etc).
Hope this helps