Dilated Pupils: Those Drops Are So Annoying

Dilated Pupils: Those Drops Are So Annoying

Dilating drops are useful tools for examining the eye.  A dilated pupil exam provides direct visualization and is the best way to examine the retina and is second to none.  The dilating drops are annoying, but are necessary.  Any and every time your doctor needs to look at your retina (or other structures such as the optic nerve), your pupils should be dilated.

Dilating drops cause mydriasis (pupillary dilation) and cycloplegia (see below).  They really have no medicinal purpose, though in certain types of inflammation, they may relieve pain.  Atropine, or bella donna, was used in ancient times to dilate the pupil as a way to accentuate beauty.  In modern times, atropine, or atropine-like medicines, are used to facilitate retinal examination, paralyze focusing ability and allow intraocular surgery.-

Retinal examination for conditions such as diabetic retinopathy and macular degeneration should be performed regularly.  The best, cheapest and most efficient way to exam treat these disease is by looking directly at the retina.  Two types of drops are usually used to effectively dilate the pupil.  Actually, the “pupil” is the opening in the iris.  One drop activates a muscle (alpha-adrenergic muscles) that runs radially (like spokes on a wheel) on the iris.  A second drop, inhibits constriction of a circular muscle (it closes the pupil like a purse-string) on the edge of the iris, thereby allowing dilation to occur, that is, in normally opposes the action of the radial muscle.

With a widely dilated pupil, a cataract can be properly identified, the optic nerve inspected for disease such as glaucoma, the retinal veins and arteries are revealed, not to mention detailed examination of the macula and peripheral retina.

Paralysis of Focusing Muscles is a secondary effect of complete dilation.  This is called “cycloplegia.”  The muscles that contract to reshape our natural lens allowing focusing for reading (and focusing at distance for far-sighted people) are paralyzed.  This wipes out close range focusing and distance focusing (for far-sighted people only).

For children, who are usually farsighted at a young age, this is an important step in properly measuring for glasses.  As the eye gets bigger, we become more near-sighted (or less far-sighted).  Thus, most average kids are farsighted and don’t need glasses in most cases.  To properly measure far-sightedness, however,  especially in a kid, the muscles need to be paralyzed.

For adults, this a very annoying part of the dilated exam – there is too much light entering the pupil and everything is fuzzy!

In most cases of intraocular surgery, such as cataract surgery and retinal surgery (aka vitrectomy), the pupil must be widely dilated to see and operate.  Pre-operatively, the same drops are given to dilate the iris/pupil at the operating room as used in the office.  The dilation can last for hours which should be enough time to get the operation done.

What Does This Mean? Dilating the eye is important because the most important structures of the eye; lens, optic nerve and retina, can only be examined by looking directly at them.  Every time a retinal examination is anticipated you should dilated.  Some docs are using non-mydriatic (aka non-dilating) equipment to see in the eye, but these devices are designed for screening purposes and are not considered detailed enough to allow a diagnostic exam.  The point is…get dilated.

There used to be drops that reverse dilation, but I haven’t seen them in a few years.  They are expensive to use and are uncomfortable for the patient.


Randall V. Wong, M.D.

Retina Specialist, Ophthalmologist
Fairfax, Virginia

  • Dick
    Posted at 17:30h, 24 February Reply

    well presented

  • Nathan Bonilla-Warford, OD
    Posted at 20:15h, 24 February Reply

    Dr. Wong,

    This is excellent. Patients often try to get out of having their pupils dilated, even when there is an increased risk of retinal problems. I think this is primarily due to a lack of understanding of what dilation is and why we do it.

    The truth is, dilation is inconvenient for doctors and patients, but it must be done for a thorough ocular exam.

    • Randall V. Wong, M.D.
      Posted at 20:24h, 24 February Reply

      Dr. Nate,

      Thanks for your input and could not agree more with your comment!


  • cna classes
    Posted at 00:33h, 01 June Reply

    well written blog. Im glad that I could find more info on this. thanks

  • Linda
    Posted at 21:45h, 18 June Reply

    Great info. I have been having my eyes dialated for years and until the last few years I have been able to get reverse drops. I was told by a technician just today that they discontinued making them with no explantion. Knowing the pharmacutical industry, it probably wasn’t a big “money maker.

    I wish I could get my eyes dialated just for the way they make my eyes look, but not the way they make them feel!

    • Randall V. Wong, M.D.
      Posted at 09:09h, 19 June Reply

      Dear Linda,

      Thanks for the comment.

      The reverse drops were a nightmare…they were expensive, burned when we gave them (so not too many wanted them), and once the bottle was opened, the whole lot had to be used quickly or the potency was lost. I think it was really the docs in the office that decided most patients didn’t want them.

      “Bella Donna,” or atropine drops, were originally used for the aesthetic effects of dilating and making a woman’s eyes beautiful.

      There are some alpha-adrenergic drops that you could ask your doctor about, but they are probably not going to be comfortable dispensing to you, but they would dilate without blurring your near vision.


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  • anna
    Posted at 17:37h, 12 January Reply

    Hi Randy!

    I was searching the internet looking for answers, and came across your article.

    My 6yr old daughter had her eyes examined by the pediatric ophthalmologist yesterday. They did the eye dilation around 1pm. This morning she complained of a headache. Throughout the day after each dose of Children’s Motrin wore off, a headache still persists. Her pupils are still dilated.

    Right now, it’s her 3rd dose of Motrin.

    The doctor never mentioned any kind of side effects. Nor it occurred to me at the time to ask.

    Is headache a possible side effect of the eye dilation procedure?

    Thank you for your time!

    • Randall V. Wong, M.D.
      Posted at 19:07h, 22 January Reply

      Dear Anna,

      Sorry for the delay, but I don’t answer these comments except weekly…at best.

      By now, I would hope you’ve contacted your pediatric ophthalmologist. Dilating drops don’t usually cause headache.


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