I know a similar product, and it's called Wartscide. I believe it has the same effect as Dermatend. As for your question, I think it would be better for you to consult with a dermatologist. We don't know for certain if exfoliating the spots would do more harm than good. Good luck to you.
Hello,
Post-inflammatory hyperpigmentation is a condition where there is an excess amount of pigment following a disease process that affects the skin. Without treatment, this usually takes about 6 months to resolve and for the skin color to go back to its normal color. Topical treatments with acids and chemical peels can be effective but can take a while for the skin to totally revert to its normal color. Microdermabrasion can also be done, but this might require several sessions. Skin resurfacing using lasers is also an option.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your dermatologist. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.