Lillib: I have a friend who is challenged with major ME and she takes extra potassium daily thru the day, it helps a LOT with energy. Adult RDA for potassium is 4700-5100mg and we get no where near that in our foods...unless one eats 6 or so avocados daily. Check this out and check with link on symptoms of low potassium. Don't overload but optimal could help you. There is a sub forum here on CFS/FM.

8 Signs and Symptoms of Potassium Deficiency (Hypokalemia)

Personally I take 200mg potassium gluconate with just about each meal daily. Labs always come in on low end of range so I am aware.

I was told I have FM years ago but also find a major connection with low thyroid and FM symptoms, CFS too.