The 8 frequently asked questions about extended wear contact lenses
Medically reviewed by Jakub Odcházel, DiS., Chief Optician, on 18 Dec 2020. Written by Lentiamo
Precise vision for the whole month without having to take out your lenses? Sounds almost too good to be true. No more worrying about blurred vision in the morning, you'd see clearly from the first blink of an eye.
But do such lenses exist? Can you wear lenses for more than a day without harming your eyes?
Yes, you can – with extended wear contact lenses.
What are extended wear contact lenses?
Maybe you have heard of them. Leave in contact lenses are contacts that you don't have to take out, as they are inserted on the first day of the month and taken out on the last day of the month. So you don't remove them from your eye before bedtime and wear them all night and all the following days and nights.
How long can you wear night and day lenses?
Theoretically, you can wear continuous lenses for a whole month. After 30 days at the latest, however, the lenses must be removed, otherwise, dirt deposits, dry eyes and possibly cornea damage may occur. Lentiamo recommends you to always consult with your eye care professional before wearing contact lenses overnight.
Can you sleep with contact lenses in?
The maximum wearing time of conventional contact lenses is between 10 and 14 hours – depending on their oxygen permeability. However, extended wear lenses (sometimes also called continuous wear contact lenses or night and day lenses) have such a high oxygen permeability that you can wear these contact lenses throughout the day and night – if your ophthalmologist or optician recommends it.
However, overnight wear isn't suitable for everyone. People with dry and sensitive eyes should rather avoid wearing contact lenses continuously. This is because contacts reduce the oxygen supply to the front of the cornea, leaving the eyes unable to fight off dirt, bacteria and corneal infections. So if you wear your lenses continuously day and night for several days, the risk of eye health problems may increase. Ask your eye doctor for advice and read the Lentiamo guide on sleeping with contact lenses.
Take a look at the best extended wear contact lenses on Lentiamo:
Who are night and day contact lenses suitable for?
Night and day contact lenses are suitable for all lens wearers whose optician or ophthalmologist has recommended them. Soft contact lenses offer a great alternative to glasses, especially for professionals who work in rotating shifts. People who work day and night are similarly affected, such as doctors working 24 hours a day, on-call or in shifts.
How do night and day lenses work?
Extended wear lenses are made of air-permeable lens material called silicone hydrogel. The oxygen transmissibility of these lenses is between 100 and 175 Dkt so the water content is quite low. Since extended contact lenses with high water content draw tear fluid from the eye, a lower amount of moisture prevents dry eyes .
Let's take a closer look at the properties of night and day contact lenses
- Very high oxygen permeability
- Integrated moisture reservoir
- Excellent surface technology
- Silicone Hydrogel Material
How do you correctly apply continuous contact lenses?
Let's say your ophthalmologist allows you to test continuous wear contact lenses.
What next? Your continuous contacts will first be perfectly adapted to your eyes by taking all the necessary parameters into account. Ideally, you test your new extended wear contact lenses on a weekend so that you can assess how your eyes react when you sleep with contact lenses. If you don't experience any discomfort or pain at night or on any of the following days, you can then test your night and day contact lenses all week without taking them out. However, if your eyes become tired and reddened, you will need to consult your optician or eyecare practitioner to find a suitable alternative.
Do overnight lenses pose a risk of complications?
Although your doctor has given you permission to wear night and day contact lenses, most opticians and eye care professionals recommend taking your lenses out one night a week to allow your eyes to relax a little. With this routine, you can wear your night and day contact lenses even when you're on vacation.
What you shouldn't do: Don't wear your regular monthly lenses longer than recommended. All contact lenses should be removed from your eye after your tested wearing period, and regular monthly disposables should be removed before going to bed in the evenings. If in doubt, always carry a pack of daily disposable lenses with you to avoid the risk of eye infection.
The risks of eye infections are also studied by Optometry and Vision Science, the results of which were published on the website of Optikum.at. The study deals with continuous wear contact lenses. It states that extended wearing of lenses is associated with a higher risk of ocular infections.
You can read more on this topic here:
Sources:1. Optikum, https://www.optikum.at/…ntaktlinsen/
2. Medizin-Aspekte, https://medizin-aspekte.de/…nsen-105538/
3. Acuvue, https://www.acuvue.de/…u_200713.pdf
