Exfoliate the skin gently 2–3 times per week
Moisturize daily with a thick cream or lotion
Use products with urea, lactic acid, glycolic acid, or salicylic acid
Apply sunscreen to knees when exposed to the sun
Avoid friction from kneeling, tight clothing, or rough scrubbing
Keep the area clean and hydrated
Try natural brightening ingredients like aloe vera, licorice extract, or vitamin C
Use retinoid creams at night if suitable for your skin
Treat underlying causes such as dry skin, eczema, or insulin resistance
See a dermatologist if darkening is sudden, severe, or persistent