Dead skin cells, on the other hand are what causes dark spots on elbows and knees. Layers of dead skin cells build up causing skin on knees and elbows to darken. For the underarm area, dark patches may be caused by friction, or by irritation from shaving or waxing.
How to treat these blotches?
If you think the spots are caused by dead skin cells buildup, exfoliation is the key to get rid of them. Gently scrub the area with a good exfoliant to eliminate dead skin cells. A skin cream that contains urea and a low percentage of glycolic acid is your answer for darkened underarms. For the face, use a cream that contains retinol. This helps turn over skin cells and can help reverse small signs of sun damage.
To prevent dark spots from recurring, ALWAYS use sun protection when going out. A sunscreen with an SPF of 30 or higher will help maintain an even skin tone because it will prevent sunlight from triggering more melanin production. And to prevent doing more harm to the skin if you have problems such as acne, cuts, or bruises; it’s best to keep your hands away. DON’T RUB, DON’T TOUCH, DON’T SCRATCH, DON’T SQUEEZE, DON’T PICK. Doing so will only traumatize the skin even more.