What causes a brown spot in eyes?

Brown or any other spots in the eyes can be caused by various diseases and conditions ranging from minor trauma to severe diseases like cancer. While there are some medical conditions where permanent damage to the eye is not likely, there are others that might result in serious damage and must be evaluated by a medical expert.

Some less severe conditions that might cause eyeball spots include:

1. Axenfeld nerve loop, which is very similar to a small freckle.
2. Horner-Trantas dots are yellowish or white rather than brown and appear near the edge of the colored part of an eye.
3. Eye-drops are crystallized drug depositions.
4. Racial Melanosis is a brown irregular shaped patch.