Preservative free saline guide

Preservative free saline matrix

 Product Buffered? Size & price Notes
Purilens Plus Yes* 4oz bottles ($15.95 for 3, $39.95 for 12, $79.90 for 24)

Most economical packaging for heavy users

Too much for people who only use a little

Same as the former Unisol 4

Sealed bottle, puncture with lid. Must be discarded within 15 days of opening

ScleralFil Yes* Box of 30 10mL vials ($17.50)

Handy size for travel

Only buffered saline sold in unit doses 

LacriPure No* Box of 98 5mL vials ($22)

Vials are easier to open than Addipak & Modudose

Only unbuffered saline labeled for ocular use



Box of 100 5mL vials ($17.50), or

Box of 24 15mL vials ($10.75)

Most economical choice.

Sold for nebulizers. Use with scleral lenses is strictly off-label and should only be done on doctor's recommendation.



Box of 100 5mL vials

Sold for nebulizers. Use with scleral lenses is strictly off-label and should only be done on doctor's recommendation.

Prescription only, not sold here


Buffered or unbuffered?

All of the salines listed above contain purified water and sodium chloride. Those also listed as "Buffered" also contain two additional ingredients, sodium borate and boric acid. Buffers are used to raise the pH of saline in order to match it as closely as possible to the typical pH of human tears; they are also used to keep the pH stable after the product is opened. Saline without buffers is more acidic to start, and becomes more so after opening.

For many users, the absence or presence of buffers does not seem to make a difference. However, for many users with dry or sensitive eyes or with an extensive history of corneal disease, the acidity of unbuffered saline seems to cause eye irritation, burning, and/or a tendency to lens fogging. Therefore, historically, those with the most complex medical histories have tended to prefer buffered salines for use with PROSE and full size scleral lenses. (Unisol 4 and Simply Saline, both now discontinued, were buffered salines as well.) On the other hand, some doctors may have concerns about the buffers themselves being an irritant for some patients. 

What size?

Many patients, especially those fitted with standard scleral lenses and using ClearCare as their only cleaning regimen, do not need a lot of saline to fill their lenses. In those cases, the 5mL sizes such as LacriPure tend to meet their needs the best. For those who do a lot of rinsing, for example, rinsing daily cleaners off PROSE, or rinsing cleaners or disinfection agents off Hydra PEG coated lenses, Purilens Plus tends to be more practical as it has the lowest cost per volume and it's the only one in a bottle you can keep for awhile. Additionally, many people use Purilens at home and single use vials when traveling.

Don't forget!

  • Make sure your eye doctor is involved your saline decisions. This is especially important for PROSE and scleral lens users, and for anyone using products "off label".
  • If you are using single-use vials, discard them the day you open them. It's not only about the risk of contamination (since they have no preservatives), but we are told that the pH of unbuffered salines drops rapidly after opening.