If you're up for a $40 test, try this stuff:
I just got diagnosed with histamine intolerance; this OTC pill breaks down the histamine in food, sort of like how Lactaid works with milk. One study they did showed like 80% of the kids with ADHD had a histamine intolerance!
I've been on a high dose for a couple months now & the difference is astounding! It didn't magically cure my ADHD, but it did remove my life-long brain fog & got rid of that "mousetrap hammer" feeling of not being able to engage in task initiation at will, which is HUGE for me!