Brief Answer:
Probably an allergic reaction due to an allergen in the work environment.

Detailed Answer:
Hello dear and welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice.

I have reviewed the attached reports and also your medical history.

The blood work results are generally normal.

I would recommend steroid shots as an alternative treatment to relieve the itching.

In my opinion the symptoms seem to be related to an allergic reaction, maybe in the work environment.

You should be very careful to notice if any allergen aggravates the symptoms.

Form further evaluation you can take a second opinion from an allergologist.

Hope I have answered your query. Let me know if I can assist you further

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