Post-Picosure hyperpigmentation is transient and will often fade on its own over a period of 3-6 months if it occurs on the face. Hyperpigmentation occurring on off-facial sites e.g. limbs will often take much longer to fade (9-24 months).
Resolution will be hastened by stringent sun-protection and use of medical-grade lightening creams.
It is prudent to avoid additional laser treatments and treatments that may further injure the skin e.g. aggressive chemical peeling as they may possibly aggravate the hyperpigmentation further.
Your attending doctor who performed the laser treatment will be the best person to guide you through this difficult period and prescribe you the necessary lightening creams.