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  #1  
Old 01-29-2010, 02:29 PM
Meltdown Meltdown is offline
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Expiration date on saline solution

I have a bottle of saline solution here in my desk at work (Bausch and Lomb ReNu MultiPlus, if it matters). I keep it for emergencies, when something gets under one of my contacts and I need to remove it and rinse it out. This doesn't happen very often.

Anyhow, I picked it up today and noticed that it expired back in 2004. Apparently it has been in there for awhile.

My question -- is it now potentially harmful, or is it just operating at less than optimal effectiveness? If it's the latter, I'll keep it around -- I don't use it for daily cleaning, only the occasional rinsing. But if it's harmful, obviously I'll spring for a new bottle.

Thanks!
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  #2  
Old 01-29-2010, 02:53 PM
usar_jag usar_jag is offline
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I am not going to vouch for whether it's safe or not. However, it is just a salt solution, and if you've treated the bottle well, i.e., not left it sitting open for it to be contaminated, I'd imagine it would be just fine for rinsing.

As an aside, my stomach was acting up earlier today, and I ingested a couple of Maalox Max tablets that expired back in 2006. No ill effects--so far...
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  #3  
Old 01-29-2010, 02:59 PM
Fact of the Matter Fact of the Matter is offline
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Generally things like saline have an expiration date for a garuntee of sterility for unopened bottles. Saline will also become hypertonic as the water evaporates. Your best bet is to spring for a new bottle.
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Old 01-29-2010, 03:03 PM
lazybratsche lazybratsche is online now
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A lot of medical or scientific products will have expiration dates for no particularly good reason. Usually, it means the manufacturer tested the container to confirm that it won't spontaneously get leaky for X years, and then stamp "date of manufacture + x" as the expiration date. Hell, even sterile empty plastic tubes (packed in a sealed, sterile plastic bag even) will have an expiration date.

So your bottle of saline is almost certainly fine, but the manufacturer didn't want to spend the money to test it and guarantee that it would last for more than a few years. There might be some slight chance that there's some sort of chemical in that solution that isn't stable, but it should pretty much just be salts and buffers which will last effectively forever.

Last edited by lazybratsche; 01-29-2010 at 03:03 PM..
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  #5  
Old 01-29-2010, 03:57 PM
Parenchyma Parenchyma is offline
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It's your eyes. Please don't risk your corneas and sight to an infection. There may be cooties growing in that solution by now. I even think it was B&L who had a fungal contamination in one brand of their (non-expired) solutions a few years ago and some people lost their vision. Don't risk it.
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  #6  
Old 01-29-2010, 04:20 PM
Dogzilla Dogzilla is offline
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Quote:
Originally Posted by Fact of the Matter View Post
Generally things like saline have an expiration date for a garuntee of sterility for unopened bottles. Saline will also become hypertonic as the water evaporates. Your best bet is to spring for a new bottle.
Dang. Even my American Heritage Dictionary didn't clear up for me what hypertonic means.
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Old 01-29-2010, 08:14 PM
twhitt twhitt is offline
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Originally Posted by Dogzilla View Post
Dang. Even my American Heritage Dictionary didn't clear up for me what hypertonic means.
Simply, too salty. As the bottle sits, seal broken and cap closed, some water will evaporate from it. The salt doesn't evaporate, so the solution that's still in the bottle has the same amount of salt as it did but some smaller amount of water than before. The remaining solution will be hypertonic, or too salty, compared to some standard level.

The evaporation would be very slow, assuming the above. But honestly, a small dropper bottle of contact lens solution shouldn't be prohibitively expensive, and as Parenchyma said, you should take care of your eyes.
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  #8  
Old 01-29-2010, 10:18 PM
Meltdown Meltdown is offline
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Quote:
Originally Posted by Parenchyma View Post
It's your eyes. Please don't risk your corneas and sight to an infection. There may be cooties growing in that solution by now. I even think it was B&L who had a fungal contamination in one brand of their (non-expired) solutions a few years ago and some people lost their vision. Don't risk it.
It's not that I'm cheap, it's that I don't like to be wasteful. It would bother me to toss out a half-full bottle of saline solution if there's nothing wrong with it. I've had the same pair of sneakers for the past 10 years.

Okay, maybe I'm a little cheap. But your point is well taken. No sense playing the odds when it comes to vision care, especially when we're only talking a few bucks.
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  #9  
Old 01-29-2010, 10:20 PM
Student Driver Student Driver is offline
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Bausch and Lomb Renu Multiplus is not a saline; Sensitive Eyes Saline is Bausch and Lomb's saline line. The additional ingredients in Renu are minor components, but could affect the safety of expired solution.

And another voice chiming in to go buy another bottle if you need some-- it's pretty cheap.
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  #10  
Old 01-30-2010, 01:56 PM
mnemosyne mnemosyne is offline
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Quote:
Originally Posted by lazybratsche View Post
A lot of medical or scientific products will have expiration dates for no particularly good reason. Usually, it means the manufacturer tested the container to confirm that it won't spontaneously get leaky for X years, and then stamp "date of manufacture + x" as the expiration date. Hell, even sterile empty plastic tubes (packed in a sealed, sterile plastic bag even) will have an expiration date.

So your bottle of saline is almost certainly fine, but the manufacturer didn't want to spend the money to test it and guarantee that it would last for more than a few years. There might be some slight chance that there's some sort of chemical in that solution that isn't stable, but it should pretty much just be salts and buffers which will last effectively forever.
Contact lens solutions are considered to be medical products and their manufacture and testing are regulated by the FDA and their equivalents in other countries. The expiration dates are based upon the stability requirements and regulations established for that type of product, and the manufacturers will have
proven that their products are good for X amount of time.

It is neither cost effective or rational to expect companies to prove stability for 6+ years more than the regulations require. Even for sterile empty plastic tubes...that packaging is proven sterile for Y years, but not more, and while there might be every theoretical reason to believe they are still safe, the fact is there is no data, no testing, and nothing at all to confirm that theory.

Odds are, a several-year expired solution for contact lenses no longer has the same concentration of ingredients in it as it had when it was made, due to evaporation. Disinfecting ingredients, if there are any, may also degrade, and it is possible for bacteria to live in ophthalmic solutions. Using an old solution can result in your lenses being less clean, and can put your eyes at risk of infection.
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  #11  
Old 01-30-2010, 03:37 PM
Getheren Getheren is offline
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Quote:
Originally Posted by Meltdown View Post
I have a bottle of saline solution here in my desk at work (Bausch and Lomb ReNu MultiPlus, if it matters). I keep it for emergencies, when something gets under one of my contacts and I need to remove it and rinse it out. This doesn't happen very often.

Anyhow, I picked it up today and noticed that it expired back in 2004. Apparently it has been in there for awhile.

My question -- is it now potentially harmful, or is it just operating at less than optimal effectiveness? If it's the latter, I'll keep it around -- I don't use it for daily cleaning, only the occasional rinsing. But if it's harmful, obviously I'll spring for a new bottle.

Thanks!
I really don't think that infection is your most serious concern here, if the bottle has been closed and kept in a dark place and what's in there is simple saline (water with inorganic salts, no organic molecules for microorganisms to catabolize). I shudder to think of some kind of superbug that can reproduce without any appreciable source of energy and nutrients. But still, if there were, the outcome could be blindness, and it's always the low-risk/high-impact scenario that wakes risk assessment experts up at 3 AM with drenching sweats. Well, that and tuberculosis.

What will almost certainly have happened is that your saline will have become strongly hypertonic by now and will burn your eyes horribly when you put your contacts in after rinsing them. I presume you don't want that.
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  #12  
Old 01-31-2010, 07:19 PM
dracoi dracoi is offline
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Quote:
Originally Posted by Getheren View Post
I really don't think that infection is your most serious concern here, if the bottle has been closed and kept in a dark place and what's in there is simple saline (water with inorganic salts, no organic molecules for microorganisms to catabolize). I shudder to think of some kind of superbug that can reproduce without any appreciable source of energy and nutrients.
It's very common for people to make the mistake of touching the dropper tip with their fingers and (even worse) touching the dropper tip to their eye. Both are excellent ways to introduce both bacteria and some food for them to grow on. And, since they'll probably be growing right on the tip, you'll have a good chance of putting a significant number of the critters straight into your eye.
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