Sure. Overdose caffeine can cause headaches and migraines and then lead to vision problems such as blurry vision, blind spots , visual hallucinations. Caffeine can get into the blood vessels, thus affect the vessels in the eyes, which can cause red eyes and shifting vision. Having too much caffeine will also affect the eye muscles and cause then to spasm. However, it is a temporary condition. Once
your body metabolizes the caffeine, the caffeine won't affect your vision.
Yes, I heard that drink too much caffeine will cause dilate of your eyes. Besides, for some people, even if moderate caffeine consumption c will cause blood sugar to rise or drop, resulting in blurred vision. It will affect the ability to see clearly, which may causes you rub your eyes or squint. In fact, aside from affect vision, take caffeine can also increased urination, loss of appetite, nausea, stomach and trouble breathing etc.