With regards to allergies, you should determine what is causing that particular allergy
(specific allergen - something you eat, breath odor or being in contact - touch).
Next, exzema is very difficult to treat especially when it is associated with allergies; therefore, you can identify yourself what is triggering such acute and/or aggravating symptoms.
As you are saying, you are running a far animal sanctuary - check if anything you keep in the sanctuary makes you aggravate the itching (when you smell or touch something).
In any case, I'd advise to talk to your physician in order to understand better the real culprit together.