My Grover's disease turned out to be a fungus. I used "Fungal Forte" (from Original Medicine or Garden of Life...both same ingredients). 1 tablet 3 X's a day for first week; then 2 tablets a day for next week. I combined this with 2 activated charcoal (to eliminate die-off which is critical, otherwise it reactivates the rash). I like Bulletproof brand. I also used herbal organic talc baby powder to keep the rash clean and dry.
Nothing my dermatologist or PCP recommended worked. Helpful to reduce or eliminate stress, overheating that produces sweat. If you want to get rid of this insidious systemic condition faster, combine with anti-inflammatory foods (avoid bread/sugar). Stick as much as possible to protein, veggies, and low sugar fruit (Granny Smith apples, blueberries). Be careful of some fruits that often have mold (strawberries). In one week there was a miraculous difference and after two weeks I'm cured!