Contact lenses and their expiration date explained
Millions of people worldwide rely on contact lenses for clear vision, ease of use and practicality. However, many users wonder if their lenses have an expiration date, and if so, what the implications are for using expired lenses so let’s jump right into it.
Do Contact Lenses Expire?
Yes, they do, even when unopened. contact lenses normally expire up to four years after being packaged. And it’s not due to the lenses themselves but because of the saline solution and packaging.
Why do contact lenses expire?
Contact lenses are made from soft, flexible materials that can degrade over time (it takes a very long time for this to happen), losing their shape, elasticity, and ability to maintain proper hydration, but the lenses can’t technically expire. However, the biggest issues are the sterile packaging that contact lenses come in can deteriorate and the saline solution can lose its form, becoming acidic or more alkaline, potentially compromising the lenses' sterility and increasing the risk of eye infections.
Manufacturers assign an expiration date to their products for a reason, to ensure that they maintain their optimal performance, safety, and hygiene. This date is typically based on the expected shelf life of the materials used, the stability of the packaging and the results of stability tests conducted by the manufacturer.
What to do if you accidentally wear expired contacts?
If you inadvertently wear expired contact lenses, we recommend you remove them immediately and discard them properly.
If the lens has just recently expired it is unlikely to cause any serious problems, however, if you notice any changes to your eye such as redness, itchiness or discharge then contact your optometrist.
The longer the gap between the expiration date and when you are wearing them will increase the risk of irritability and or infection.
In a study (published in The South African Optometrist) on the safety of expired lenses researchers found some contamination in expired lens packs.
What issues can arise if I suddenly start to decide to wear expired contact lenses?
Several. Don’t do it. Wearing expired contact lenses can lead to a variety of potential issues, including the following:
- Reduced visual performance and comfort
- Eye irritation: Deteriorated materials can cause you to suffer irritation, redness or itching. Your lenses may feel uncomfortable to wear and you may experience pain.
- Infections: The sterile environment of the lens packaging could become compromised which increases the risk of you getting a bacterial, fungal, or other microbial infection.
An untreated eye infection can lead to serious eye problems, always see an eye care professional or a Doctor if you think you may have an eye infection.
How do I find my expiration date?
You can find the expiration date of your contact lenses on the packaging, it is normally printed on the individual lens foil packs and the outer box. The date can be represented in the American form YY/MM or the European form MM/YY. This can cause some confusion so if in doubt ask the supplier of your lenses. Make sure you check the date before using the lenses and discard any expired products immediately.
How to dispose of expired contact lenses
Expired contact lenses should be thrown away in the trash. Do not try to flush them down the toilet, this can contribute to microplastic pollution and you could potentially harm aquatic ecosystems. It's also a good idea to recycle the lens packaging whenever possible.
Can I use an expired contact lens solution?
No! We do not recommend using an expired contact lens solution as its disinfecting properties may diminish over time. This can compromise the hygiene of your lenses and increase the risk of eye infections. Always check the expiration date on the bottle and replace any expired products with fresh solutions. Also remember to change your solution after one month of opening, although the bottle may still say it's in date once the solution is exposed to air it is no longer sterile and over time bacteria and microbes can contaminate the solution
Am I able to purchase expired lenses?
No, Optometrists and suppliers of contact lenses check their stock regularly to make sure they do not sell expired contact lenses. A reputable supplier will make sure you have plenty of wear time left in your lenses- for example, if you buy a pack of 6 monthly disposable lenses then the supplier will make sure you have 9 months before expiration.
Should you inadvertently receive a supply of contact lenses that are out of date, contact the supplier immediately for a replacement.
How long do contacts last before they expire?
The shelf life of your contact lenses depends obviously on the type and brand. In general, unopened soft contact lenses have a shelf life of between two to four years from manufacture. Although this can vary, it's essential you always refer to the expiration date printed on the packaging to determine the exact shelf life of your lenses.
Contact lenses do indeed expire and using them past their expiration date can lead to several health issues, including discomfort, reduced vision quality and potentially serious eye infections. It's crucial you always remember to:
- Check the expiration date on your contact lenses and solution before use.
- Dispose of expired contact lenses properly by throwing them away in the trash and recycling the packaging when possible and if possible of course.
- Avoid using expired contact lens solution as its' disinfecting properties may be compromised.
- Purchase your contact lenses from trusted sources.
- Consult an eye care professional immediately if you experience any discomfort or any complications from accidentally wearing expired lenses.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 22 Apr 2023, Last modified: 24 Apr 2023