During this year's GSLS meeting in Las Vegas, I spent quite a bit of time discussing salines with scleral lens providers, and reflecting on how things have changed with preservative free saline solutions for scleral lenses in the past five years - what we've learned, and what new products have been launched, and what the implications are for us scleral lens users. I will be blogging separately about that at dryeyezone.com, but I wanted to blog here on the shop about some of the conclusions I came to and why, because it affects what we're choosing to sell here at dryeyeshop.com and how we describe them.
My first decision - one of several - was to start phasing out inhalation solutions (a/k/a Addipak and Modudose) from the Dry Eye Shop.
Not trying to scare anybody, so please relax :)
I just want to generate conversation about filling solutions for scleral lenses, and I want to prompt leaders in the field to study and publish the effect of filling solutions on the ocular surface.
It's high time we had some actual science on this topic available to us.
Are inhalation solutions harmful?
Not that any of us knows of!
I have no reason to believe these inhalation solutions is harmful to our eyes. There is no published medical literature saying so. (There's also not much literature about anything on this topic at all, for or against.)
Then what's the issue?
And why am I taking a step that I know will be controversial and may even offend some of my doctor friends?
Here are three things I would like to ask you to consider regarding inhalation solutions, which you will be familiar with under names like Addipak and Modudose and any other similar brands of unbuffered 0.9% sodium chloride solution.
1. Using inhalation solutions in scleral lenses is OFF LABEL.
Inhalation solutions (Addipak and the like) are used in nebulizers for inhalation therapy. They are not packaged, tested, or labeled for ocular use.
Scleral lens use is complicated.
Solutions for scleral lens use are complicated.
We patients, new and old, get confused with all of these solutions.
This problem is compounded when we are given solutions whose labels don't make sense, and whose instructions we cannot follow safely. - Unless, of course our doctor has provided detailed written instructions for us... but that is the exception rather than the rule.
Solution labels contain information and instructions that we scleral lens users often have to disregard or ignore. We are often given special instructions verbally that we cannot be expected to remember in full. This situation is unacceptable. Inhalation solutions are one little part of that problem that is easily solved. Why not do it?
In medicine in general, many doctors prescribe drugs for "off label" purposes when that's the best choice for their patient's well-being. That is a recognized and vital practice. After a product is approved by the FDA, more science evolves and we learn more about what a product can do for some people and doctors have to have the freedom to prescribe what they feel we need, beyond the product's original labeling.
If your doctor is familiar with all the options and is specifically recommending Addipak for you, that's none of my business and I have no issue with it!
But if Addipak is being recommended to every scleral lens patient, I'm now questioning that as a broader practice, because there are now ample PROPERLY LABELED alternatives readily available, including unbuffered sodium chloride (Lacripure) which theoretically is the same thing - even the same size package, but properly labeled.
Why recommend off label without a specific reason?
2. Inhalation solutions are ACIDIC.
Inhalation solutions are believed to have a pH of apprx 5 to 5.5. That's very acidic. But does it matter?
Is it just a question of what's comfortable? What feels good?
Or are there any medical implications of holding acidic solutions against our eyes all day? Is pH balanced better medically? Or does it literally not matter at all? Or does it matter for some people?
As with so many other things about scleral lenses, we don't know, and while there's no apparent reason for us to be scared of what we don't know, when scleral lenses are becoming this prevalent, and are being used on healthy eyes too, it's about time we started knowing. There are enough industry dollars kicking around for people to do their homework, figure it out and tell us.
There are both broader and more nuanced questions about filling solutions to be discussed, of course. It's not a simple question of the "right" pH, by any means. Even anecdotally, pH balanced salines are certainly not a panacea. Buffering agents themselves can apparently cause problems for some patients. We patients are mixing all kinds of cocktails in our lenses, partly because no single solution is solving our problems, but also because no one has answers for us so they encourage us to 'experiment'.
We need more answers - more science.
3. Inhalation solutions were a convenient STOP GAP that evolved into prevalent usage.
Addipak has been used in scleral lenses for a long time, but why? It's not designed for ocular use. As discussed, it's not labeled for ocular use. So why?
One key reason is because for a long time there weren't any unit dose preservative free saline solutions approved and labeled specifically for contact lens use. Additionally, for a time during 2016 after the infamous discontinuation of Unisol 4, amidst Purilens shortages and before any of the newer unit dose salines came to market, there were no properly labeled preservative free salines of ANY kind available, so we really didn't have much choice.
But everything has changed since then.
There are now four different preservative free saline solutions on the market labeled for contact lens use, three of which are labeled specifically for scleral lenses (see below). It's time to move on from off-label non-ocular products in situations where there is no compelling reason to recommend them.
What are the reasons in favor of inhalation solutions?
My evil twin's first sarcastic thought about this is: Why aren't all of us dry eye patients using the veterinary form of cyclosporine, with a script from our doctor, instead of forking out hundreds of dollars in Restasis co-pays? After all, it's cheap, and there's probably more published science about its effects than there is about Addipak.
Down, evil twin!
We don't all need cheap. We have corneal diseases. We need safe and effective, and we need clear written instructions that keep us safe and promote success in our lenses.
Some of us definitely do need cheap. I care a lot about the financially strapped corneal disease community. This is the community I have worked with on a daily basis for a great many years. But is the financial argument sufficient justification for recommending off label products to everyone indiscriminately? Maybe not so much.
What are the PF saline options?
We've come a long way since Unisol 4 and Simple Saline bit the dust! Hurray, we have options!
- LacriPure is an unbuffered sodium chloride solution in 5mL vials. This is the most similar to Addipak/Modudose in both type and size, although based on a report or two we understand the pH to be significantly higher, like ab out 6.5. (The manufacturer makes no claims about its pH.) This was the first properly labeled PF saline in unit-dose containers.
- ScleralFil is a buffered (pH balanced) solution in 10mL vials. This was the first buffered PF saline available in a unit dose.
- Nutrifill is a new buffered (pH balanced), electrolyte-enriched solution in 10mL vials.
- Purilens is a buffered (pH balanced) solution in 2oz and 4oz bottles. Filling sclerals with Purilens is an off-label use and the labeling (such as the directions to discard 15 days after opening) may not be appropriate for scleral lens users. If you are using Purilens, it's very important to consult your doctor about how long it is safe to keep these bottles open. More about this soon! - Meantime, personally, I LOVE the Purilens minis. I use a 2oz bottle in about two days, so I don't worry about critters growing in it.
So what about cost?
And the fact that preservative free salines are not sold in drugstores remains a huge problem. It means we have to deal with shipping costs in addition to everything else, and it means we have to plan ahead.
But all these things are part of the cost of using scleral lenses and frankly we all find ways to deal when we have to.
Top suggestions for savings:
- Buy in bulk? If you're paying shipping, the shipping cost is proportionally far, far higher on a single box of anything. Always buy at least two or more at a time.
- Subscription saline purchaser? Instead of one box every month, buy two boxes every two months, or three boxes every three months. The incremental shipping cost to add a box is typically only $1-$2.
Dry Eye Shop phase-out of inhalation solutions
We will continue offering inhalation solutions at dryeyeshop.com for a while (probably a few months) as we have many subscription (auto-ship) customers and we want to make sure we don't inconvenience them too much. If you have a subscription order for one of these products, we will be getting in touch some time soon, but don't worry about anything being stopped suddenly.
This 'rant' is not about whether inhalation solutions are harmful.
It's about taking steps to hold optometry and the industry to a higher standard.
NOTHING here is intended as a criticism of your scleral lens provider or of their saline recommendation. YOUR eye doctor knows YOUR eyes and so long as YOU are being regularly examined and are compliant with instructions, there is NO reason to believe that there is any saline issue here affecting you. And if Addipak or Modudose is the right thing for you, there are many great sources to choose from!
My bottom line is this: The solutions we use in our lenses - solutions bathing our diseased corneas all day long - should start to have real science backing them, not just endless anecdotal evidence and clinical experience.
It was one thing when scleral lenses were a niche treatment used by a handful of top tier specialists for rare diseases. But today, scleral lenses are making their appearance throughout non-specialist optometry practice, and they're being used on healthy eyes too. So the questions and the issues are very, very different. We must have better standards of care.
We are discontinuing inhalation solutions here at the Dry Eye shop to make a statement, for educational reasons and to hopefully generate more conversations between patients and doctors (maybe even between doctors and doctors!) about patient instructions, and the complexity of scleral lenses, about PF saline pH, about prioritizing our ocular health, and about the need for scientific evidence for scleral lens filling solution recommendations.
p.s. There's lots more to come in this conversation, so stay tuned!