My sister(dark skinned; hispanic) had an IPL treatment done and she had burn On her entire cheeks. Thankfully, the blusters healed well and the darkened areas peeled off okay. My main concern is the possible PIH Over the areas that have scabbed off. She had melasma over the cheeks and that was the reason why she had the IPL treatment. it's only been 2 wks since the treatment and we are so concerned of the PIH. when can my sister start using hydroquinone ointment?