Options for lightening the skin of knees and elbows include chemical peels, laser surgery and home remedies such as sunscreen, lemon juice and the use of a topical lightener, according to Everyday Health. Cutting a lemon in half and rubbing it on the discolored area is one common home remedy.
The juice of a lemon can remove dark coloring on elbows and knees and restore the natural skin color, according to Women's Health Magazine. However, Everyday Health Magazine warns that people with sensitive skin may have an adverse reaction to using lemons as a skin-lightening treatment. The same type of reaction may occur due to excessive scrubbing of the skin with a loofah or net pouf. The added friction can cause skin irritation and increase the risk of damage from sun exposure. Dermatologist Dr. Jeanine Downie advocates in Everyday Health magazine the use of products containing 2 percent hydroquinone as efficient in making skin tone more even. For a natural alternative, she suggests the use of products containing licorice, kojic acid and soy to even out skin discoloration.
Downie suggests that a doctor evaluate the progress a month after any treatment in order to avoid lightening the skin past its original color.