Concussion. Shock. Both require a 911 call. Hopefully is covered with your insurance.

It could be a number of things, some very serious I would consult a Doctor A.S.A.P!

Brain issues. Are your pupils dilated in bright light?

Before you decide to exclude drugs as a cause, how have you arrived at that determination? If the person / victim is saying it, then he could still be lying – or even unaware. So there could still be (even if some drug screenings are done) drugs or other toxins that you just don’t know about yet. So I’d be maintaining a certain skepticism that “it’s not drug-related” until a positive determination is made about some other cause.

Some simple eye examinations require that the examiner enlarge the pupils with eye drops, so that’s one simple explanation.

Drops at the eye doctors to dilate pupils prior to an exam.

Oops! @CWOTUS Just read that you said the same thing.

I don’t know if this is a sudden thing or a long term thing you are talking about.

I have huge pupils all the time. I used to wonder if it was the meds I am on. But then I looked at pictures of myself from way before I started taking them. Apparently I have always had “dilated” pupils. Some people just have them.

Also excitement, focus, arousal, low light…

ETA: My pupils aren’t ALWAYS wide, just as a usual state. I mean, they do react to lights and stuff.

Thanks all, that helps. I’m not the one with the dilated pupils, by the way.

Would you say a 6 month old baby is probably excited/ focused on all kinds of things a lot, unlike older people who are bored where it’s same old same old to them?

Would you please describe the situation that prompted this question?

….I take that back. I don’t know if focus/excitement would cause dilated pupils. People around children would have noticed it and it would have been common knowledge.

What prompted this question @flo?

A related question.
https://www.fluther.com/204624/at-what-age-would-a-child-know-enough-to-be-scared/