We received an observation from FDA regarding to our callus remover product saying that Potassium Hydroxide was used as a drug and we failed to test strength..the intention was to make this a cosmetic product. I am confused, but the observation may be because Potassium Hydroxide has a USP monograph? or our label says "Extra strength" or Professional formula?.. I will appreciate any advice. The cosmetic guide does not provide such details about this. Thank you!!