Brownish discoloration of the fingernail is one among the symptoms of fingernail fungus. The change in color is due to the formation of colored pigments produced by fungus. The immune system of our human body finds it difficult to destroy the fungal infection because immune cells dare to reach into the nail where fungi breed and create infection. You can use hydrogen peroxide solution to get relieved from both pain and fungus. Bleach your infected fingernails with peroxide solution to prevent fungus from breeding. It is an economical fingernail fungus cure that can be used by people very easily.