how to flatten keloid scars?

Answer 1

To flatten the scar and make it softer it can be injected with small amounts of corticosteroids. It won't get rid of it completely but it will help significantly. Unfortunately its not a on time treatment, and will need to be repeated several times usually over 4 week intervals. Side effects are local only being that only a small amount is injected in.
To get rid of it completely, you would usually have to have a surgery to remove it. If its a keloid (as opposed to a hypertrophic scar), the chance of it returning is quite high, and doctors would usually add a second treatment after surgery to reduce the chance of it from recurring (like injecting the cortisone or applying compression with or without topical cortisone, a cream called aldara, a pulse dye laser may also be an option.)

Answer 2

1

Answer 3

By a laser.
And you can only do so by the hand of a professional Doctor.
Preferrably one who has done many of these, you don't want to fool around and cause more damage.