Needing a prescription for glasses is a bit absurd to begin with. The worst case of wearing the wrong prescription is that you'll get a headache. I suppose it could be a bit dangerous if some drivers were slightly disoriented, but I can't imagine glasses being more dangerous than something like Tylenol.
If I need a new pair of glasses with the same prescription I have now (Say, for example, I fall and break my glasses), I shouldn't be required to go get examined to get a new pair simply because it has been more than a year. I want the same thing I've been wearing, and the worst possible outcome from me getting them is that (if my prescription has worsened, which it hasn't in 4+ years) I can't see quite as clearly at long range as I ought to.
That doesn't make much sense because adult vision doesn't change much. It should be perfectly valid to use an old prescription unless you want to re-check your vision. I've never seen this law in Asia or Europe and people are living just fine.
> The worst case of wearing the wrong prescription is that you'll get a headache.
Doesn't using the wrong prescription worsen eyesight faster?
At least, it's been my general experience that when a child is curious about people's glasses and is given the glasses so they can experience the effect, they only let them try it for a couple seconds and are explained that using them for too long can cause damage to their eyesight (because it's the wrong prescription for them who have perfect eyesight). Is that a myth?
Yes, it's a myth in the sense that you would need to wear the glasses several orders of magnitude longer and/or consistently for there to be any negative effects. Some people seem to think that even looking through the glasses will unleash demons into the healthy eye.
Modern research does point in the direction of the eye remodelling itself based on what kind of input you give it on a longer scale, though. This includes the amount of light seen during the day and whether it is able to focus rays or not. There are indications these play a role in the development of myopia.
The eyes don't care about what's in front of it. The brain does the image processing, so that's the only thing that's affected by a bad prescription. If your glasses are so wrong that it causes eye strain, it may cause damage, but you'd have to purposefully put yourself into that ordeal.
No... It's not like I've seen it only once or never talked about it with other people. It's general common sense or a common belief, even if it turns out to be false.
Tylenol (acetaminophen) is probably a pretty good example. They both seem pretty safe in reasonable situations (a slight difference in prescription value, a couple hundred extra MG dose) but can be hugely problematic at greater levels (lethal/permanent liver damage or completely unable to see anything with a terrible prescription)
Which brings up another benefit of using an online eyewear vendor: they let you type your own prescription in. If you are personally fine with using a two-year-old prescription, do it.
When I ordered glasses a year ago, I also played around with the idea of eliminating astigmatism from my prescription by adjusting the cylinder value to 0 (it was only .25 in one eye and .50 in the other) and offsetting the sphere value by half of the difference. Because their buy-one get-one free sale, I got one pair with astigmatism and one without, and got to decide which I liked better.
That's awesome. Anything more than about a half diopter and you'll probably not get away with that in glasses. Contacts can go a little higher. I'm personally astigmatism sensitive, so I have to be spot on for degree and diopter.
To be legally above board, an online provide must attempt to confirm the Rx you enter is correct AND still valid. But few if any do because its a race to the bottom on quality and price. At Topology Eyewear, we spare no expense to ensure you get the best custom frames (like a custom suit) AND the best optics money can buy. We take 100% compensated Rx very seriously!
It depends on the vendor. Warby Parker, for example, requires you to scan/upload the prescription given by your doctor, which obviously has a date on it. I guess it's always possible to just edit out or change the date on it though.
My insurance fully covers annual exams, so that doesn't bother me too much. If the period between covered exams was longer than the prescription period, yeah, I'd be peeved.
I thought it was a state thing. But it's apparently an FTC rule that started with contacts and was expanded to glasses as some point.
Not that I would advocate anyone taking shortcuts on eye exams, but assuming online US providers insist on appropriate documentation and doctors' names, there's always ordering from Canada.
my glasses prescription doesn't have an expiration date on it. Zenni and Coastal don't care if I order new glasses using my old prescription. I haven't tried with contacts... I think my last prescription had an expiration date.
Note on contacts: because you're physically inserting a medical device into your eye, part of your annual exam is making sure that you are not causing any (potentially permanent) damage do your eye. While hopefully you are not abusing your contacts, even in normal use, sometimes the eyes can be harmed, which can cause major problems down the road for you. In my opinion, the expiration is probably a good thing if you're proponent of trying to protect people's eye health.
Significant change isn't just the RX, it is other things that can go wrong in the eye as well. IF caught early it can be corrected, otherwise you may not notice until you are half blind.
That's true of everything, though. Your grocery store doesn't say, "sorry, you haven't been to the dentist in 6 months, we can't sell you food", even though there are many dental issues that can be life-threatening if not treated and eating food makes it worse. It's not their business to care.
