Hi,
Skin hyperpigmentation occurs when an excess of melanin(the component that decides and regulates the color of skin, hair and eye) forms deposits in the skin resulting in darkening it. Mostly face and neck.
Melasma, Freckles, Photo
Melanosis,
Tanning, Photo Melanos etc are the different types of hyperpigmentation.
You can use following remedies -
1. Raw Potatoes - Cut raw potatoes into slices, put few drops of water on it and rub it over pigmented skin area. Wash it off with luke warm water after 15 minutes. Do this 3 times a week for a month and see the results.
2. Lemon and Honey - Take a juice of 1 lemon and 1 teaspoon honey in a bowl. Mix it well and apply on affected area. wash it off with normal water after 15 minutes. For better results, do it twice daily.
There are more remedies that can help you reduce your skin hyperpigmentation. Refer this link - http://blog.defineaesthetics.com/what-is-skin-pigmentation-its-causes-treatments/
There are some simple treatments available for skin pigmentaion like chemical peel,
microdermabrasion etc. You can get more information here - http://www.defineaesthetics.com/skin-pigmentation-treatment-pune.php