Slightly unequal pupil size

I've noticed when I'm fatigued or have not worn my glasses (farsighted) at night, my left pupil is slightly larger than my right. When light is shone in each they react normal. During the day they look fine. However, very rarely in the mornings my right is slightly bigger than my left. It's typically when my left eye is dry in the morning, and within an hour or so they're back to normal. I'm seeing an opthalmologist in 2 days. Any ideas? My eyes feel healthy and I'm my health is fine.

[Ray T Oyakawa, MD]

The focusing of your eye can make you pupil slightly smaller If you are hyperopic (farsighted).  The near response includes focusing for near, smaller pupils, and convergence of your eyes (looking toward your nose).

Dr. O.

[Ray T Oyakawa, MD]

The focusing of your eye can make you pupil slightly smaller If you are hyperopic (farsighted).  The near response includes focusing for near, smaller pupils, and convergence of your eyes (looking toward your nose).

Dr. O.

[andrewhick52]

I am farsighted, and I've been told I have an astigmatism in my left, I believe. When I look at my reading glasses the left eyeglass is stronger than the right.

What would account for the mornings when (sometimes) the right is slightly bigger than the left?