Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain it seems that darkening of the face,neck and hands seems to be most probably due to sun tanning as these are sun exposed areas of the body and regular exposure can cause darkening of the skin.. The treatment that can be done is a combination of topical depigmentation creams and certain techniques along with prevention of sun exposure.. You can start washing your face with Salicylic acid and glycolic acid containing facewash.. You can apply creams containing Kojic acid, glycolic acid and arbutin.. Vitamin E and C containing creams can help.. Creams that are rich in licorice extract and grapeseed extract can be helpful.. Always apply a sunscreen lotion to reduce photosensitivity effect.. You should exfoliate your skin twice a week with a gentle face and body scrub.. You can also take steam twice a week and gently scrub the skin with a soft towel so as to remove dead skin as wekk as it nourishes the skin by removal of toxins and improves complexion.. Treatments like chemical peeling, Photofacial, Microdermabrasion, dermal rollers etc can be helpful.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.