People often do not realize that contact lenses have expiry dates like medical products, because, they are in fact medical products. It is not very unusual to mistake the expiration date of a medical product like an aspirin but you need be more a lot more careful when you are dealing with contact lenses. You will find the important information on the packaging and please read them through.
Odds are high that you only once in a while take a gander at that date, for a couple of reasons: it’s only a cluster of numbers on a little bundle, you do not know anything about why the expiry date matters, and for the most part the expiry dates are long enough that standard users utilize all of their lenses well before the expiry date. Even if you do not fully comprehend why the expiry date is important, complying with it is an essential piece of having lenses in a secured manner.
Contact lenses can expire while they are still packaged. Before they leave the manufacturer the last thing being done is sterilizing. Once the lenses are sterilized they are put in an air sealed package and this seal is not immortal. It will go a few years just as strong but will eventually give up. At that point, air will find its way to the lenses and contaminate them.
Why can’t we just wear the expired contact lenses you might ask. Well, for a few reasons. First is the one we just talked about, air getting into the contact lenses and the solution, might result in growth of bacteria. We believe no one would want to put anything in their eyes that contain bacteria. the solution itself can be very dangerous if it has been exposed to air, the acid level will rise up and can potentially harm your eyes.
You should also avoid contact lenses that are not too far from their expiry date. Assuming they have been on the shelves for a long time, being moved all the time without anyone buying them, the chances are that the air seal is compromised.
Besides the shelf life, contact lenses are made for different purposes with different use time once they are out of the package. There are disposable lenses that you can only wear for a day. Those ones do not need cleaning or solution as you only wear them once. Other ones can be used for a week, month or more in some cases. They will be more expensive and require constant cleaning and care. With price comes convenience, you can wear these ones while you sleep without harming your eyes a bit.