The generic drug is Pyridostigmine. I started taking 1/4 of a 60 mg tablet morning and night for a week, then 1/2 a tablet morning and night for a week and now i'm on a whole tablet. I am being treated by the Columbia Presbyterian long covid clinic in NYC. The effects were almost instant on the full dose. I was in great shape before covid 5' 4" weighing 125 lbs, then migraines, dizziness, sensitivity to light and sound, etc. My cardiologist sent me for a sleep study, (< less than 5 apneas) and i gave the machine a 6 month trial before boxed it up and hid it in my closet. Being of a certain age 55 yo, i also started Hormone Replacement Therapy (through midi.com) and the estrogen patches and progesterone (100mg) at night helps with sleep and anxiety.

I hope you find relief!