My child's eyelid started drooping suddenly: when it is urgent

The first question that matters about a drooping eyelid is not how bad it looks. It is when it started. A lid that has hung a little lower since babyhood is one story. A lid that was fine last week and is not fine today is a different one, and it is the one that should not be left waiting.

That does not mean panic. It means a clear, calm plan: what makes this urgent, what can wait, and what to do tonight.

My child's eyelid suddenly started drooping. Is this an emergency?

It needs to be seen today, but it is not a reason to panic. A droop that has appeared over hours or days is on the NHS list of eyelid problems that need urgent medical help, alongside an eye that cannot be opened or kept open. Phone, and go the same day.

Go straight to the nearest hospital emergency department if the droop comes with any of these: one pupil larger than the other, an eye that will not move properly or sits turned down and out, double vision, a headache, being sick, a recent knock to the head, a high temperature, or a child who is simply unwell. Tell the triage staff the words "sudden droopy eyelid". Those words tell them why you are worried.

The reason for hurry is not that the outlook is usually bad. It is that the cause decides the treatment, and some causes are easier to deal with early.

Why would a child's eyelid suddenly droop?

Because the muscle that lifts the lid, or the nerve that tells it to work, has been interrupted. The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) says a droopy eyelid, called ptosis, happens when the muscle that lifts the lid is weak, and that an acquired droop can come from problems with the brain, the nerves or the eye muscles.

The list of named causes includes myasthenia gravis, Horner syndrome and a third cranial nerve palsy. For that nerve, AAPOS lists head injuries, infections, vaccines, migraines, brain tumours, aneurysms, diabetes and high blood pressure among the causes of a third nerve palsy that appears later in life. The list is not there to frighten you. It shows why "wait and see" is the wrong plan for a new droop, and why an examination has real work to do.

This article gives no odds. No figure that could be trusted was found for how often a new droop in a child has a serious cause, and a percentage made up would be worse than none. The pattern is more useful: a new droop is seen today, and a new droop with the signs above is seen at once.

It is worse in the evening and better after a nap. What does that mean?

It can mean a problem where the signal from nerve to muscle tires with use, called myasthenia gravis. It is a reason to be seen, not a diagnosis. AAPOS describes eye symptoms in this condition as changing from day to day and getting worse as the day goes on, for example a droopy lid or double vision in the evening but not in the morning.

Myasthenia is only one cause on the list, and this pattern does not prove it. But it is a clue worth reporting, because it is easy to miss and easy to mislabel. A published case report described a two-year-old with both lids drooping for five months, better after sleep. He had first been labelled as having a droop from birth and advised to have lid surgery. A detailed history, an examination and blood tests led to the right diagnosis.

In Asian children the question deserves a little more attention. A 2022 review found ocular myasthenia four times more frequent among Asian children than among European children. And in a cohort of 343 Chinese children with childhood-onset myasthenia, 96.2% began with eye signs, and 87.8% began with a droopy lid alone. 15.1% had a respiratory infection beforehand. Those are figures from children who already had the condition, so they tell you how it often starts, not how likely it is in any child with a droop. A doctor and sometimes a neurologist can confirm it with blood tests and other tests.

So photograph your child at different times of day, with the eyes looking straight at the camera. A few phone pictures in the morning and again at night will tell the doctor more than a description can.

Is this the same as the droop some babies are born with?

No, and the difference is the date. A droop present from birth, congenital ptosis, is a lid that has always sat lower, and it is a very different clinical problem from one that has just appeared. The article on the droop babies are born with covers it properly.

A lid that has always drooped still matters, though, because vision can suffer. AAPOS warns that a droopy lid can press on the front of the eye and change its shape, making vision blurred or wavy, that a child may tip the chin up to see under the lid, and that if the lid covers the eye completely, light cannot enter and vision does not develop. A lid that covers part of the pupil should be seen within days. A mild droop that leaves the pupil clear can be booked routinely, and it still needs one proper check.

How do you tell old from new? Look at photographs. Scroll back through your phone to the last picture in which the lids look level, and to the ones from six months ago. If you cannot find a time when the lids were even, that is a useful thing to tell the doctor, and the child should still be seen.

What else should I look at when I check her eyes?

Look at the pupils and at how the eyes move, in ordinary light. These are the two checks that can turn a "this week" into a "today", and neither needs equipment.

Compare the two pupils. A droopy lid with a smaller pupil on the same side is the pattern of Horner syndrome, which a review defines as a droopy lid, a smaller pupil that still reacts, and sometimes less sweating on that side. It has its own page, one pupil bigger than the other. A droopy lid with a big pupil that does not react to light points the other way, towards the third nerve. AAPOS says a droopy lid or a big pupil might be the first sign of a third nerve problem, and that the eye might look down and out.

Then watch the eyes move. Hold a toy at eye level and slowly walk it to each side, up and down. Watch whether both eyes reach every corner. Young children usually do not say they see double, and AAPOS notes that a droopy lid can hide the double vision, so what you can see matters more than what you can ask.

If a lid looks droopy because it is swollen, red or hot, that is a different problem with its own urgent list, in a swollen eyelid in children.

Who do we see, and how fast?

Today, and an eye doctor if you can, but never delay a same-day sign for the sake of the right doctor. If any of the signs in the first section is present, go to the nearest emergency department and say what you have seen. If the droop is new but nothing else is wrong, phone a hospital eye service or a paediatric eye clinic and use the word "sudden". A GP or klinik kesihatan can also examine and write a referral letter, but a new droop should not wait for that letter to be processed.

An examination measures how far the lid opens, looks at both pupils, watches each eye move and examines the eye itself. Whether blood tests or a scan follow depends on what the examination finds.

A new droop should not be watched for a week. The NHS lists a sudden droop among the eyelid problems that need urgent medical help.

Common questions

References

1. AAPOS · Ptosis (droopy eyelid) · aapos.org
2. AAPOS · Third nerve palsy · aapos.org
3. AAPOS · Myasthenia gravis · aapos.org
4. NHS · Eyelid problems · www.nhs.uk
5. Frontiers in Pediatrics · Clinical characteristics and outcome predictors of a Chinese childhood-onset myasthenia gravis cohort (2022) · www.frontiersin.org
6. Frontiers in Neurology · The epidemiology and phenotypes of ocular manifestations in childhood and juvenile myasthenia gravis: a review (2022) · www.frontiersin.org
7. GMS Ophthalmology Cases · Early onset bilateral juvenile myasthenia gravis masquerading as simple congenital ptosis (2017) · pmc.ncbi.nlm.nih.gov
8. Eye and Brain · Horner syndrome: clinical perspectives · pmc.ncbi.nlm.nih.gov

By Dr Chan Li Yen. General information only. It does not replace a consultation. If you are worried about your child's eyes or vision, please see an eye doctor.