There is such a thing as a low histamine diet. Tons of good helpful info online. Basically, some foods trigger histamine reactions (fatigue, skin issues, itching, etc). Certain people react differently to some histamine-producing foods, so some trial and error is needed.
There's a great book entitled What Hit Me - Living With Histamine Intolerance. It's available on Amazon.
My daughter experiences histamine reactions from some foods (they're not allergies, they're classified differently), and reducing the histamine foods has helped.
It's a fairly simple way of eating - no strange things to buy or crazy foods to eat. So you might look it up online and try following a low histamine food plan for a few weeks and see if you find some relief.