Hi Amp. Good question. Generally speaking, we let patients know that brown spots from ingrown hairs dramatically decrease after 3-4 visits because the coarse dark hair that causes the ingrown problems is the first hair to be removed with laser hair removal. In cases where patients do not want to wait for the permanent hair removal, we step in with hydroquinone bleaching products.As an aside, if your skin gets brown spots from ingrown hair, then IPL may not be the best technology for permanent hair removal. IPL is abroad spectrum of light and much less effective than Diode, Alexandrite or Yag lasers for permanent hair removal. And with medium to dark skin types, IPL carries a much higher risk for side effects from hair removal treatments. Best of luck.