when there is a dark line along the bridge (top) of the nose it is often due to allergies and rubbing the nose. the gold-standard skin brightener is hydroquinone. the typical prescription-strength products contain 4% hydroquinone. it can be irritating to your skin though so your dermatologist will review if this is the right treatment for you and how it should be used for your condition. over-the-counter products can contain up to 2% hydroquinone but i believe this ingredient should only be used under the supervision of your dermatologist.
for the last year i have been facing the problem with a black line on the left side of the nose. how can i remove this?