Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain it seems that he is suffering from post inflammatory hyperpigmentation secondary to Acne or pimples.. I would suggest that he should start washing his face with depigmenting facewash like AHA Glow or Melaglow that contains Salicylic acid and glycolic acid as main ingredient.. You can start applying creams containing Kojic Acid, arbutin.. Azelaic acid containing creams are also helpful.. You can apply Retinoid based creams like Adapelene once at night.. Vitamin E containing gels and lotion are also effective.. You should scrub your face with a face scrub twice weekly.. Take Vitamin C supplements. You can go for treatment like Chemical peel and Microdermabrasion and Dermal rollers.. Avoid excessive sun exposure as it can cause darkening of spots.. Drink plenty of water.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.