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Sleeping in Contact Lenses: A Kiwi's Guide to Extended Wear Contact Lenses

19th Jun 2025

LensesOnline Sleeping in Contact Lenses A Kiwi's Guide to Extended Wear Contact lenses

Ever wondered if you can sleep in your contact lenses? Maybe you're tired of the nightly routine, work irregular hours, or have a busy lifestyle that makes daily lens care challenging.

The good news is that some modern contact lenses are specifically designed for extended and continuous wear. But it's important to understand the differences, benefits, and considerations before making the switch. Here's everything you need to know to make an informed decision.

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What's the Difference? Extended vs. Continuous Wear

The terminology around overnight contact lenses can be confusing, so let's break it down simply:

Extended wear is the broad category for any contact lens approved for overnight use. This includes lenses you can sleep in for anywhere from one night up to 30 nights, depending on the specific lens type.

Continuous wear refers to lenses at the top end of this range - typically those approved for up to 30 consecutive nights without removal.

In practical terms:

  • Some extended wear lenses are approved for 1-6 nights
  • Others (continuous wear) are approved for up to 30 nights

Your optometrist has to determine which duration is appropriate for your eyes.

Here in New Zealand, Medsafe regulates all contact lenses as medical devices following international standards. The specific wear duration comes down to each manufacturer's testing and approval with international bodies like the FDA.

The key point is that any overnight wear - whether it's one night or thirty - requires lenses specifically designed and approved for sleeping in. Regular daily lenses should never be worn overnight, regardless of how comfortable they feel.

The Science Made Simple: Why Some Lenses Can Handle the Night Shift

Your cornea needs oxygen to stay healthy. During the day, it gets plenty from the air through your tears. But when you're asleep with your eyelids closed, oxygen has to pass through the lens itself.

This is where the magic number "Dk/t" comes in – think of it as your lens's breathability score. It's oxygen permeability (Dk) divided by lens thickness (t). Traditional hydrogel lenses typically score around 30, which isn't enough for safe overnight wear. Modern silicone hydrogel lenses often score 100-175 or higher, allowing much more oxygen through.

LensesOnline NZ Guide to Extended Wear Contact Lenses Low Oxygen Versus High Oxygen Flow

Without enough oxygen, your cornea can swell, develop new blood vessels, or worse – develop ulcers. Even in high-UV countries like New Zealand (our summer UV index can hit 12-13), material choice trumps everything when it comes to overnight oxygen supply.

Who Benefits Most? 

Lifestyle How Extended Wear Lenses Help Best practices
Shift Workers & Professionals Eliminate the hassle of lens care during irregular hours and overnight shifts Strict adherence to follow-up schedule - 1 week, 3 months, 6 months after fitting, then every 6 months
Frequent Travellers Maintain a clear vision in challenging environments like flights, hotels, and remote locations Pack essentials like  sterile saline, rewetting drops, and backup daily lenses for flexibility
Parents & Busy Lifestyles No interruption to vision during unpredictable schedules and night-time care duties Set phone reminders for lens changes and keep spare daily lenses as backup

The Safety Reality Check

Let's be transparent about the risks and benefits. Research consistently shows that sleeping in contact lenses increases the risk of eye infections compared to daily wear, like daily contact lenses. However, modern extended wear lenses are specifically designed and rigorously tested for overnight use.

The key factors that make overnight wear safer today include:

  • Advanced silicone hydrogel materials with high oxygen permeability
  • Improved lens designs that maintain eye health during sleep
  • Better understanding of proper fitting and follow-up care
  • Strict regulatory approval processes for overnight wear claims

Important symptoms to watch for:

  • Unusual eye pain or discomfort
  • Persistent redness or irritation
  • Discharge or excessive tearing
  • Sensitivity to light
  • Feeling like something's stuck in your eye

If you experience any of these symptoms, remove your lenses immediately and contact your optometrist. Most issues can be resolved quickly when caught early.

Extended wear contact lenses for Astigmatism

Toric lenses for astigmatism can work for extended wear, but there's an extra consideration: lens rotation. Even with clever stabilisation designs, the pressure from your eyelids during sleep can cause the lens to shift.

Continuous wear contact lenses for astigmatism options include:

Your optometrist will need to check lens position and comfort more frequently, and you might need occasional lens-free nights to reassess the fit.

4 Best extended-wear contact lenses in 2025

Real comfort comes down to how the lens actually feels when you wake up at 4 am or after a long shift. Here's what New Zealand wearers are saying about our top performers available through our store, LensesOnline NZ, based on verified customer reviews and real-world experience.

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1. Air Optix Night & Day Aqua (Alcon)  

Our customers give this lens a rock-solid 4.8/5 rating, often saying that they can “forget about taking lenses out every night.”

Why it wins: FDA-cleared for 30 consecutive nights of continuous wear, and still delivers a Dk/t of 175, thanks to a slick plasma surface that shrugs off deposits. Current price: NZ$ $92.95 / box of 6.

2. PureVision 2 HD (Bausch + Lomb) 

Many of our customers note crisp vision “even after a 12-hour shift.”

Tech & value: Balafilcon A plus AerGel keep these extended wear lenses thin and breathable; at NZ $59.95, it’s the cheapest true 30-night option on our continuous wear contacts range.

3. Biofinity (CooperVision) 

A hefty 240 reviews with the same 4.8/5 rating satisfaction score as Air Optix, buyers repeatedly call it “great value and super comfy.”

Why people like it: Aquaform® locks water into the Comfilcon A matrix, so it feels soft right through its 6-night/30-day schedule. Price holds at NZ $65.95.

4. B+L ULTRA

Early adopters like how “eyes feel fresher late in the day.”

Edge: MoistureSeal® tech claims 95 % water retention over 16 h, approved for 6-night wear. Mid-pack price: NZ $82.95.

Specialised Options:

5. Biofinity Toric

Our customers praise how the lens “stays put and doesn’t rotate.”

Stand-out feature: Optimised Toric Design plus the same breathable Comfilcon A gives cylinder powers up to −2.25 D, a reliable 6-night sleep-in route. Costs NZ $111.95 per 6-pack.

6. PureVision 2 for Astigmatism 

It’s the only toric lens cleared for a full 30 nights of continuous wear, using B+L’s Peri-Ballast geometry. List price NZ $108.95.

7. PureVision Multifocal

Our customers highlight the joy of “no reading glasses in the middle of the night.”

Design notes: Balafilcon A with centre-near/centre-distance zones lets you sleep in and still read your phone at 3 a.m. NZ $141.95 for 6 lenses.

8. Biofinity Multifocal 

Most customers say the near-far transition feels “seamless.”

Why it’s liked: Two balanced ADD profiles (D & N) on the comfy Biofinity base material; approved for 6 nights. Sits at NZ$ $123.95.

Prices and review counts are indicative only and may change without notice. 

Remember, these customer experiences provide valuable insights, but your individual eye health, lifestyle, and comfort preferences are unique. Always consult with your optometrist to determine which lens type and wearing schedule is safest and most suitable for your specific needs.

FAQ

Can I sleep in lenses if I have dry eyes? 

Generally not recommended. Overnight wear makes dry eye symptoms worse and increases your risk of complications. Chat with your optometrist about lubrication strategies, or consider daily disposables with planned removal instead.

Do extended-wear contact lenses block UV? 

Most soft lenses don't provide adequate UV protection. Always wear proper sunglasses, especially in New Zealand, where our summer UV index regularly hits 12-13.

How often do I need check-ups? 

In New Zealand, the standard schedule is one week, three months, and six months after fitting, then every six months thereafter. This might seem like overkill, but it's your best protection against serious complications.

Can I wear continuous wear contact lenses on long-haul flights? 

Yes, they're actually handy for avoiding lens-handling hassles in cramped aeroplane loos. Use rewetting drops for comfort and remove them if you experience any discomfort.

What if I accidentally nap in daily disposables? Even a short nap counts as overnight wear, which increases infection risk if your lenses aren't approved for sleeping. Ideally, remove them before any sleep or switch to approved overnight lenses.

The Bottom Line

Extended or continuous wear lenses can be brilliant for the right person in the right circumstances. They're particularly valuable for shift workers, travelers, and anyone whose lifestyle doesn't mesh well with daily lens routines.

But they're not a set-and-forget solution. Success depends on choosing the right lens, following your wearing schedule religiously, maintaining excellent hygiene, and keeping up with regular check-ups.

The technology has come a long way – today's silicone hydrogel continuous lenses are safer and more comfortable than anything available even a decade ago. But your eyes are irreplaceable, so always work with a qualified optometrist to determine if continuous wear is right for you.

Remember: this information is educational and shouldn't replace professional advice. Always consult with your optometrist before making changes to your contact lens routine.

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