How often does a child need new glasses? Outgrown frames, scratched lenses and a changed prescription
The glasses still sit on the nose, so surely they are fine. Here is how often to re-check, the signs a pair has stopped working, and what to do about frames, scratches and the old pair.
- A school-aged child is usually seen about once a year, and sooner if the number is changing. Your eye doctor sets the exact interval.
- Squinting, holding things close, sitting near the screen, headaches or "the glasses do not work" mean book the check now.
- A frame that is too small, bent or slipping puts the lens off centre in front of the pupil, so fit matters as much as the number.
- Scratches matter when they sit in the line of sight. Keep wearing the old pair until the new one is ready, and keep it only as a spare, not a hand-me-down.
- A stronger number means myopia has moved. If it moves a lot or keeps moving, ask about myopia control.
The glasses still sit on the nose, so surely they are fine. But a child grows every month, and so does the eye. A pair that was right a year ago can be too small, too loose or too weak for the eye today, and a child rarely says so.
How often does a child who wears glasses need the prescription checked?
Usually once a year, and sooner if something changes. The American Optometric Association says a school-aged child should have an eye examination every year, or more often if there are specific problems or risk factors. The exact interval for your child is the one your eye doctor sets, because it depends on why the glasses were prescribed.
I know of no published schedule giving one interval for every child already in glasses, so I will not invent one. A young child with glasses for a squint or a lazy eye (amblyopia) is usually seen at shorter gaps than an older child with a steady, small number. A child whose short-sightedness (myopia, rabun jauh) is moving is seen more often than either. For a progressing myope, the international myopia guidelines advise review at least every six months.
The action: book the next check before you leave the room. What happens after a child is told they need glasses explains the first steps.
How do I know the glasses are no longer right?
Your child will show you before they tell you. Squinting, holding a book or tablet close, sitting near the screen or television again, tilting the head, headaches after school work, or saying the glasses "do not work" are all reasons to book a check now, not at the next routine date.
The American Optometric Association lists frequent headaches, tiredness or discomfort, holding reading material close to the face and losing the place when reading among the signs of a vision problem in school-aged children. Children often think the way they see is the way everyone sees, so a blurred board may never be reported.
A child who takes the glasses off to see a screen is also telling you something: the number may have changed, or the frame may have slipped. Either way the answer is a check and a fit. How to tell if your child needs glasses goes through these signs by age.
Keep one more thing apart from this list. A sudden change in vision, a new squint or an eye that turns is not a reason to wait for a routine date. Those are on the warning list at the end of this page.
My child's frames look too small or bent. Does that matter?
Yes, because a lens only works properly when the eye looks through the right part of it. The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) says a frame should be comfortable with each eye centred behind the lens. A frame that has slipped, twisted or become too small moves the eye away from that centre.
The centre of the lens, the optical centre, is made to sit in front of the pupil. When the frame is too small, too wide or bent, the pupil sits off to one side or low in the lens, and the child sees through a part that was not made for that eye. The Association of British Dispensing Opticians lists glasses sliding down the nose, looking over the lenses, discomfort and reduced vision from a lens in the wrong position as results of a poor fit.
A National Health Service hospital leaflet adds that a narrow frame can let a child look over the top of the lens, where there is no correction at all.
It is also normal for the fit to loosen with daily wear. The leaflets I read say children's glasses may need adjusting regularly, and that fit checks should continue as the child grows. Take the glasses back to the kedai cermin mata (optical shop) when the pads leave marks, the arms bend outward or the glasses slide down on their own.
The action: an adjustment is often the whole fix. If the frame is simply too small, a new frame with the same lens power solves a fit problem, and that is still worth doing.
Do scratched or damaged lenses need replacing?
If you can see the scratch when you look through the lens, or your child complains of glare or smudges that will not clean off, yes. A scratch in the line of sight is a flaw in the picture.
Children's lenses are plastic because they are less likely to shatter than glass, and the same hospital leaflet says that plastic lenses may be more prone to scratches. The dispensing opticians' association adds that scratch-resistant coatings help lenses last longer, though no lens is fully scratch-proof. So scratches are expected; the question is whether they sit where your child looks.
Habits matter more than coatings. Wash the lenses with water and lens cleaner, not a dry rub on a T-shirt, keep them in the case, and do not set them down lens-first. A bent frame or a lens that has popped out is a visit to the shop the same day.
The action: hold the glasses up, look through them at a lamp or a window, and check the part in front of the pupil. If it is cloudy or marked, ask the shop whether the lens can be replaced in the same frame.
Can my child keep wearing the old prescription for a while?
For a few weeks while you wait for a check or a new pair, usually yes, and wearing something is better than wearing nothing. Unless your doctor has told you otherwise, keep the old pair on. AAPOS says wearing glasses does not worsen a child's eyesight, so an old pair does not harm the eye.
What an out-of-date pair does is give a less accurate picture. It may leave the board blurred or strain the eyes. For a child whose glasses treat a squint or a lazy eye, I would not leave a long gap, and I would call the clinic and say the child's glasses are due. For a child with a number that has been steady, a short wait for an appointment is an ordinary thing.
The action: do not stretch it out for months, and do not stop wearing glasses to "rest the eyes". Book the check.
What should I do with the old pair?
Keep it as a spare in the school bag or at a grandparent's house, if it is still intact and the number is not far from the new one. Do not hand it down to a younger brother or sister, because a pair is made for one child's eyes and one face.
A prescription is individual. Even siblings can have different numbers, different astigmatism and a different distance between the pupils. A pair made for one child will not centre in front of another child's pupils, and the lenses are not the right power.
A spare is useful on the day the main pair is lost, snapped or being repaired. Once the numbers drift apart, the old pair stops being a useful spare. Label it with the date so nobody confuses the two. For a toddler who is only just learning to keep glasses on, glasses a toddler will keep on has ideas that apply to a spare as well.
Does a new, stronger number mean the myopia is getting worse?
Not necessarily. A stronger number means the myopia has progressed, but how much it moved in the year is what matters. A small step can be ordinary growth. A big step, or the same step again and again, is the reason to ask about myopia control.
Annual change is often put at about half to one dioptre, faster in younger children. A pooled analysis found about 0.8 dioptre in a year in Asian children around age nine. The international guidelines also list progression above 0.50 dioptre a year as a marker of faster change later. A dioptre (D) is the unit behind the "power" on the receipt; reading your child's myopia prescription explains how to read it.
Fresh glasses fix the blur but do not slow the eye. If the number has changed more than your doctor expected, or your child is young when it began, ask about it at the next visit. How fast is too fast sets out the yearly change by age, and slowing myopia down compares the options without promising results. A useful question for the doctor: "How much has the number moved, and is that more than you expected?"
- Your child's vision changes suddenly, in one eye or both.
- An eye turns in or out, or a new squint appears.
- Your child has eye pain, or light has become painful.
- Your child sees double, or a part of the picture seems to be missing.
- Your child has a bad headache with sickness or a change in vision.
Common questions
How often should a child's glasses be changed?
How do I know if my child's prescription has changed?
My child's glasses are too small. Do I need a new prescription?
Can a scratched lens harm my child's eyes?
Can my child wear the old glasses until the new ones arrive?
Can my younger child wear an older sibling's old glasses?
Does a new, stronger number mean my child's myopia is getting worse?
- American Optometric Association · School-aged vision, 6 to 18 years of age · www.aoa.org
- American Association for Pediatric Ophthalmology and Strabismus · Glasses for children · aapos.org
- Royal Devon University Healthcare NHS Foundation Trust · Children's glasses patient information leaflet · royaldevon.nhs.uk
- Association of British Dispensing Opticians · A guide to selecting children's glasses · www.abdo.org.uk
- International Myopia Institute · Clinical management guidelines (Gifford et al., 2019) · pubmed.ncbi.nlm.nih.gov
- Donovan et al. · Myopia progression rates in urban children wearing single-vision spectacles (2012) · pubmed.ncbi.nlm.nih.gov