Skin pigmentation comes as a result of many reasons and some of them include: direct exposure to sunshine, skin damage from injury, allergic reactions among other reasons. This can be treated at home and there's no need of visiting the doctor.Some of the remedies include: Using a raw potato. Raw potato contains an enzyme called catecholase. This enzyme inhibits one's malanocytes curbing excessive melanin production. All you have to do is slice the potato into half then add few drops of water and then rub the potato in circular motion in the affected area with lukewarm water.Do this twice a day for one month. In case it does won't work then consider using lemon juice but mix it with honey and repeat the exact procedure from above. Something else you have to do is, avoid direct contact with the sun, maintain high personal hygiene and finally take a balanced diet.