5.Why It Happens: Medicine or Chemicals
Certain drugs — including some that treat heart disease, high blood pressure, erectile dysfunction, nervous ailments, or emotional disorders — can have colorblindness as a side effect. Colorblindness also can come from working around chemicals like fertilizers or solvents. But while things like taking certain drugs or working with certain chemicals can cause secondary color deficiency, it is very uncommon.
6.How It’s Found
If your child is colorblind, you may not know it until they start to learn the names of colors. Or they may have a hard time in school with exams or homework that use color-coded materials. It’s a good idea to test kids’ color vision around age 4. If colorblindness runs in your family, have your child tested by an eye doctor.