Dark brown coloring of the knees is often also associated with some thickening of the skin. In most patients, it would be due to a condition called post-inflammatory hyperpigmentation due to friction from clothing or kneeling on the area for many years. It is more common in people with darker natural skin color.

The most important part of treatment is to reduce friction, rubbing, or injury to the areas that are darkening. The irritation can also be reduced with the use of cortisone creams such as hydrocortisone or stronger ones that require a prescription from a doctor.

The addition of a daily moisturizing lotion such as Eucerin or Cerave can help. Avoiding sun exposure is also important. Bleaching creams are usually not helpful.