👉 Tyrosinuria is a condition in which the body produces too much of a protein called tyrosine, which can cause problems with vision. Tyrosinuria is usually caused by an increase in the production of tyrosine in the brain. The symptoms of tyrosinuria include blurry vision, redness or pain around the eyes, and difficulty seeing colors. Treatment for tyrosinuria often involves adjusting the diet to reduce the amount of tyrosine produced by the body.