4. Different Sized Pupils
Pupils are normally the same size in each eye. They let in light so you can see, which is why they get bigger when it is dark. Having big pupils when it is dark is not a problem, but having one pupil that is bigger than the other pupil is a problem. Different sized pupils indicate that someone is at high risk for having a stroke or a brain aneurism. They also can indicate a brain or optic nerve tumor. Obviously, you want to take different sized pupils very seriously. If you do notice that you or someone else has different sized pupils, it is very important to see a doctor.