My son's left eye's pupil is bigger, should I be worried?

My son is 3yrs old and his eye does not stay like that permanently only occasionally, he has had no head injuries...

Hello there!
Anisocoria refers to a difference in pupil size and 20% of normal people may have as much 1mm of difference. What your son may have is known as "simple anisocoria" and the pupil sizes in such individuals commonly change from day to day and even from hour to hour without any serious underlying cause.
There are other causes of this such as:
Horner's syndrome, third nerve palsy, adie pupil, stroke, iris damage and certain medications.
It is very normal for people to have different size of pupils.... but in saying that you should take your son to see a doctor to rule out any possible serious underlying causes...especially since he is so young :)

yes of course your son has a problem!!!! take him to a doctor!! NOW!!!!

He is tripping on LSD, take him to the park asap, and bring some Pink Floyd for the ride there.

Let an opthamologist take a look at him.

talk to a doctor.....but it may be a drug hes on

i strongly suggest that you see your son's pedeatritian.
different sized pupils usually suggests pressure on the brain......that could be dangerous.

Take him to an optometrist who may refer you to an opthamologist.

This is important to do now when he is young. The reason is - he may have a condition called ambylopia (medical term) or lazy eye. If he has this condition, he sees much better out of one eye than the other and this will get worse as he gets older.

It is important to deal with this when he is young. If he does have this condition and it is caught when he is young, it can be corrected by putting a patch over his good eye for a period of time and forcing his bad eye to work. His vision can be corrected when he is young but if you wait until he is older, his eyesight will be set for life and it will be impossible to have good vision in both eyes.

Yeah, I can recall someone having a child with a brain tumor and said that the size of the puil is the reason they initially brught their child to the doctor. iT is probably nothing, but just in case bring him to the doctor, better safe than sorry.

no, don't be worried...my daughter's eyes were exactly the same way when she was three & four. i went to a doctor and he said it was totally normal...your son will grow out of it.

you do need to ask a eye dr.

ok..i just typed www.pupil.com,and their is an article about 1 pupil being a different size.They say it is serious underlying cause.anywways..please read about this,i hope it helps.

now i feel embarressed,i just read brookie and i feel bad,i hope i'm not overreacting..sorry.

The fact that the difference in pupil size is not seen all of the time, would cause me some concern. Evaluation of the pupil's reaction to various stimuli, physical examination of the pupil and other structures in and around the eye and, perhaps, other neurological examinations should be done. Take your son to an eye doctor for an examination. I would not take this lightly until major disorders have been ruled-out, particularly if the condition suddenly appear recently.

Pupils get larger and small depending on what you are looking at. Bring him to a doctor or eye doctor if his pupils stay large permanently.

you probably want to check that out quick with a medical doctor.