Redworms have young that resemble strongyloides in several of their symptoms, like headaches.
Threads like strongyloides also cause this fog.
Try getting - clove bud oil - and test the body with drops in tiny locations for several weeks. this pattern can tell you if there are red worm areas, where strongyloides congregate.
I believe, get rid of reds, threads become a mute topic, but still not sure. Depends on immune system strength.
The meds for reds and threads are a bit different in pattern, dose, and game plan.