Fill & rinse
Preservative-free saline
Goes in your eye
Sterile and preservative-free only. One vial per fill; throw the rest away.
Disinfect & store
Hydrogen peroxide system
Only after full neutralizing
Only in the case that came with the bottle. Wait the full time. Never fill the bowl with it or rinse with it before insertion.
Disinfect & store
Multipurpose / GP solution
Not for filling the bowl
Use one made for rigid (GP) lenses. Fresh solution every night, never topped off.
Comfort
Preservative-free drops
Over the lens, as directed
Rewetting drops go over the lens, as your fitter directs. Adding anything to the fill is their call.
Nothing
Water of any kind
Never on lens or case
Tap, bottled, distilled, filtered: none are sterile enough. Not even to rinse the case.
The fluid in the bowl of your lens is the only thing that touches your cornea for as long as the lens is in. That is why it has to be sterile and preservative-free, and why “only sterile saline, never water of any kind” is the rule the FDA gives for rinsing.[1] Inside that rule, there are a few real choices. This page walks through them, using what people who wear sclerals report alongside what the makers’ own labels say.
Brands are named as examples of products wearers use, not as endorsements. Use the product your fitter recommends.
The main types of fill
| Type | Examples | Good for | Watch out for |
|---|---|---|---|
| Single-use vials, buffered | ScleralFil[6] | Filling and rinsing; many sensitive eyes like it | Open a new vial each fill |
| Single-use vials, unbuffered | LacriPure,[8] Tangible Fill[9] | Filling and rinsing; plain salt water | Some eyes find it stings or reddens by evening |
| Preservative-free bottle, buffered | PuriLens Plus[5] | Less waste; easier with wet hands | The bottle has a discard date once opened |
| Insertion solution with lubricants | Cleadew SLi[10] | Wearers who want a thicker, cushioning fill | Single use; not a disinfectant; not sold everywhere |
| Respiratory (inhalation) saline | Addipak,[11] McKesson | Off-label stopgap some fitters allow | Made for nebulizers, not eyes |
Vials or bottles
Single-use vials are the usual choice. A report of Acanthamoeba infections in scleral wearers recommended sterile saline, preferably single-use, and warned against topping off.[4] LacriPure’s maker, for example, says to discard the vial after each use and not reuse it.[8] ScleralFil is listed as single-use and sterile in the federal device database.[7]
Preservative-free bottles use a sealed design that is pierced when you first open it. PuriLens says to discard any remaining solution 14 days after opening.[5] Many wearers and fitters use an opened bottle for filling for a much shorter time than that and for rinsing afterward, because nothing in the bottle stops germs once air gets in. Ask your fitter what window they want you to use, and write the opening date on the bottle.
A few fills add lubricants. Cleadew SLi, for example, lists hypromellose and sodium hyaluronate among its ingredients, is preservative-free and single use, and its instructions say it cannot disinfect lenses and must not be used for storage.[10] Wearers who use it often describe it as cushioning.
Buffered or unbuffered
Unbuffered saline is just purified water and sodium chloride.[8] Buffered saline adds ingredients that balance pH. PuriLens and ScleralFil both use a borate buffer (boric acid and sodium borate).[5][6] PuriLens’s maker explains that buffers mimic how your tears handle changes in pH, and that people with sensitive or dry eyes may notice a difference.[5]
What wearers report is that it really does vary:
- Many people whose eyes are red, sore, or burning by evening say switching to a buffered fill helped.
- Others fog quickly with every buffered fill and stay clear with plain unbuffered saline.
- Some react to one buffer and not another, or to one brand’s added electrolytes.
- Eyes change. A fill that worked for years can start to sting, and one that failed before can work later.
Thicker drops in the fill: off-label
Adding a few drops of a thicker, preservative-free lubricant to the bowl before topping up with saline is one of the most discussed habits among wearers. Refresh Celluvisc is the product people name most often. Its label describes a preservative-free, single-use eye lubricant, carboxymethylcellulose 1%, to be put in the eye and the container discarded once opened.[12] It is not labeled as a lens filler, so using it in the bowl is off-label.
Why people do it: many report less fogging, a more cushioned feel, or fewer small bubbles. The downsides people report: blurred vision, especially with larger amounts; a smeared film on the lens; stinging on a very dry or damaged cornea; and cost. Some eyes fog more with it, not less.
This is your fitter’s call. Fogging and dryness can come from the fit, the surface of the lens, or your eye’s health, and a drop in the bowl can mask a problem your fitter should see. Don’t add anything to the fill, including serum tears or a prescription drop, unless your fitter has said to. Never use a drop from a multi-dose bottle in the bowl unless your fitter specifically approves that product.
Respiratory saline: off-label
Unit-dose 0.9% saline sold for nebulizers comes up often because it can be cheaper or easier to find. Wearers most often mention Addipak and McKesson-brand inhalation saline. Using either as a lens fill is off-label: Addipak’s FDA clearance, for example, is for nebulizer and airway use, and its maker describes it as intended for inhalation only.[11] Many wearers use these products, and some fitters are comfortable with them as a filler while others are not. If you are thinking about it, ask your fitter first, and use a fresh vial for every fill as you would any other saline.
Bubbles and fogging: usually not the saline
Wearers often blame a new fill for bubbles, but bubbles mostly come from technique: not filling to a dome, flinching, or lifting the head too soon. See filling the lens and avoiding bubbles. Fogging is more mixed. Fill choice can play a part, but fit and debris are common causes too. See midday fogging.
If this isn’t working for you
| What you notice | What wearers commonly ask their fitter about |
|---|---|
| Stinging or burning within minutes | A different buffer type; better rinsing after cleaning or disinfecting |
| Red or sore eyes by evening | Buffered instead of unbuffered saline; a midday remove-and-refill |
| Fog within the first hour or two | A fit check; whether a thicker drop in the fill is right for you |
| Fogging that gets worse with buffered fills | Trying an unbuffered saline |
| Blur after adding a thick drop | Using less, or a thinner preservative-free drop |
| Itchy or mucusy eyes after a switch | Whether you are reacting to the new product |
Change one product at a time, and only with your fitter’s go-ahead. Several wearers found a reaction only by switching one thing and waiting.
Do
- Use sterile, preservative-free saline your fitter recommends.
- Open a fresh vial for every fill, and fill to the brim.
- Rinse multipurpose or GP solution off with sterile saline before filling, unless your fitter or the label says otherwise.
- Write the opening date on any bottle.
- Take the lens out if it burns or stings when it goes in.
Don’t
- Use water of any kind, even to rinse.
- Top off or reuse an opened vial for a later fill.
- Fill with multipurpose solution, preserved saline, or hydrogen peroxide.
- Pour saline into a smaller travel bottle.
- Change your fill or add drops to it without asking your fitter.
Mistakes that come up again and again
These are common, and easy to fix once you know.
- Saving an opened vial. It feels wasteful to throw saline away, but an opened vial is not sterile anymore.[4]
- Filling with drugstore saline. Many people who burned for weeks were filling with a preserved saline. Check that the label says preservative-free.
- Not rinsing off multipurpose solution. These solutions contain preservatives or disinfectants that shouldn’t sit in the bowl.
- Grabbing the peroxide bottle. Hydrogen peroxide must be neutralized in its own case for the full time on the label, and never used to rinse or fill a lens before insertion.[3] Most peroxide bottles have a red cap as a warning.[3] Keep it away from your saline. Some saline vials also look a lot like drop vials, so check before you fill, especially if your vision is poor.
- Storing lenses in saline. Saline does not disinfect. LacriPure’s maker warns that storing lenses in saline can cause serious, sight-threatening infections.[8]
- Stretching a bottle past its date. Use bottles within their discard window.[1]
- Homemade drops or saline. Never. The FDA warns against homemade saline.[1]
Some fills have been recalled, including several lots of Nutrifill in 2025 because the product may not have been sterile.[13] See shortages, recalls, and counterfeit saline for how to check what you have. For the whole kit, see saline and solutions.
Common questions
Can I save the rest of a saline vial for later in the day?
No. Once a single-use vial is open it is no longer sterile, and there is no preservative to protect it. Open a fresh vial for every fill. If you hate the waste, some fitters say the leftover can be used to rinse a lens before it goes into its disinfecting solution, but not to fill it again.
Is buffered or unbuffered saline better?
Neither is better for everyone. Buffered saline is adjusted to sit closer to the pH of your tears, and many wearers with dry or sensitive eyes find it more comfortable. Others fog or sting with buffered saline and do better with plain unbuffered saline. If your fill stings or your eyes are red by evening, ask your fitter about trying the other type.
Can I use the big bottle of saline from the drugstore?
Usually not for filling. Most large bottles of contact lens saline contain a preservative, which would sit against your cornea all day. Check the label. A preserved saline may be fine for rinsing a lens before it goes into its disinfecting solution, but the bowl needs a preservative-free product.
Can I add Celluvisc or another thick drop to my fill?
Many wearers do, often because their fitter suggested it for fogging or dryness. It is off-label: those drops are labeled as eye lubricants, not lens fillers. Thick drops can also blur your vision. Ask your fitter before you try it, and let them suggest the product and how much.
What can I fill with if I run out?
Call your fitter first. They may have samples or a local option. Wearers in a pinch have used preservative-free artificial tears from single-use vials or pharmacy respiratory saline, but both are off-label, and a short stopgap is not the same as a new routine. Never use water, multipurpose solution, or homemade saline.
Do bubbles mean my saline is wrong?
Usually not. Bubbles mostly come from technique: not filling to the brim, hesitating, or tilting the head. If bubbles start appearing in a lens that used to be fine, or late in the day, tell your fitter, because the fit may have changed.
Why does my new saline sting?
Some people react to a particular buffer or ingredient, and a lens rinsed poorly after cleaning can also burn. Take the lens out. If the stinging stops, rinse well and try again with a fresh vial. If it keeps happening, or the burning does not stop once the lens is out, call your fitter.