So about 2 years ago I was on a type of medicine which caused blurred vision as a side effect. Once the medication wore off (was on for a 4 week period) the side effects went away. However that following FAA physical, I noticed a hard time passing the color vision test, a problem I had never had before.

For the past 2 years I've had a tough time passing the color vision test and the condition hasn't improved.

I know there are alternate color vision tests allowed by the FAA to be taken (light signal tests?) but I have no idea how to go about finding the name of such tests or where I could find information on the approved facilities that provide the tests. Does anyone have some experience regarding this alternate testing?

-wise.