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Use lotion on your knees everyday to reduce dryness. Wear sunscreen every day to prevent sun damage and hyperpigmentation. Apply a chemical whitening cream or gel to treat dark knees.
Apply a moisturizing lotion every morning and evening, focusing on your knees. Look for lotions that contain petrolatum as an ingredient, which forms a protective barrier on the skin to trap moisture.  Dryness is one of the most common causes of dark skin throughout the body. If you stop applying moisturizer regularly, the dark spots on your knees may return. If you have a darker skin tone, you may be more susceptible to skin damage and scarring on your knees. Each morning, apply a sunscreen to your knees, especially if you’re wearing shorts, a skirt, or a dress. Many experts recommend that   While it’s not easy to reverse hyperpigmentation or scarring, you can prevent it from getting worse by wearing sunscreen. In some cases, using sunscreen can even remove dark spots entirely! If you do have permanent dark spots, look for a whitening cream that contains 2% hydroquinone as an ingredient. Rub the cream on your knees everyday for 4-6 weeks for the best results.  For people with sensitive skin, hydroquinone can cause inflammation. If you feel a burning or tingling sensation when you apply the cream, rinse your knees with cold water immediately. Avoid using lightening creams for longer than 6 weeks. They can cause skin irritation and damage to the outer layer of skin, and long-term use of whitening cream has been linked to certain types of cancer.