How do you remove potassium permanganate stains?

Answer 1

"Hard scrubbing with water or scrubbing with Sodium Bisulfite solution." Good answer! It worked like a charm. I used saturated sodium bisulfite, aqueous. I've gotten the habit of first trying Nochromix in concentrated sulfuric acid for cleaning laboratory glassware. This doesn't work at all for glass bottles which have contained an aqueous solution of 1% potassium permanganate for many years. So I doubt that the other answer here, namely, to use lemon juice, would work at all since this is a much weaker acid than sulfuric. Caution: If you don't rinse out the sulfuric acid before trying sodium bisulfite, you must do this in a fume hood or a well-ventilated area since SO2 gas (or some other nasty respiratory irritant) evolves.

Answer 2

Scrub your tongue, after brushing. The stain will be removed in some days.

Answer 3

with water!