So my first thought would be sodium deficiency. Potassium sort of cancels out sodium, if you aren't getting a lot of sodium then you can't tolerate much potassium. I usually don't even mention this since your average American eats 2.3 large Pizza Hut pizzas per day.
Consulting with the AI, I am told that a magnesium deficiency could also cause this, or potentially an imbalance between copper and zinc.
I can't imagine not supplementing magnesium. If I could only choose one supplement/peptide/med for the rest of my life, it would have to be magnesium. My body goes to hell about three weeks after I stop taking it. Doctors Best or Now Foods magnesium glycinate are great.
Copper and zinc, I also have experience with. Supplementing zinc (and molybdenum which is in some NAC supplements) can cause a copper deficiency. I took zinc for many years and didn't heed the warnings, and I ended up giving myself MCAS because of the copper deficiency. My first time taking 2.5mg chelated copper made me feel high. Now, the deficiency is corrected and I supplement zinc most days, then I take a break and supplement copper (because zinc inhibits the update of copper).
I definitely recommend a trace mineral supplement if you don't take one. Zinc, copper, selenium, boron, all geeat stuff.