This activity is supported by an unrestricted educational grant from Alcon, Inc.
The Role of the Pharmacist in Improving Outcomes in Patients Using Contact Lens Cleaning Solutions
Lucio Volino, PharmD
Clinical Assistant Professor
Pharmacy Practice and
Ernest Mario School of Pharmacy
Rutgers, The State University of
New Jersey Piscataway, New Jersey
Danielle Candelario, PharmD
Clinical Assistant Professor
Pharmacy Practice and
Ernest Mario School of Pharmacy
Rutgers, The State University of
New Jersey Piscataway, New Jersey
The following contributors have no relevant financial relationships with commercial interests to disclose.
Lucio Volino, PharmD
Danielle Candelario, PharmD
Pharmacy Times Office of Continuing Professional Education
—David Heckard; Steve Lin, PharmD, RPh; Maryjo Dixon, RPh
Editorial Staff—Kirk McKay and David Allikas
An anonymous peer reviewer was part of the content validation and conflict resolution. The peer reviewer has no relevant financial relationships with commercial interests to disclose.
After participating in this activity, participants should be able to do the following:
Recognize the prevalence of contact lens use worldwide and in the United States, as well as the types of contact lenses available and the types of wearing schedules.
Identify contemporary contact lens cleaning accessories and the risks associated with the use of soft contact lenses.
Recognize high rates of nonadherence and reasons for nonadherence as they relate to contact lens cleaning solutions.
Discuss information vital for use in managing patients using contact lens cleaning solutions, including effective patient counseling strategies regarding risks, appropriate use, the importance of compliance, and how and when to consult specialists.
Type of activity
: December 12, 2013
: December 12, 2015
Estimated time to complete activity
: 2 hours
Pharmacy Times Office of Continuing Professional Education is accredited by the Accreditation Council for Pharmacy Education (ACPE) as a provider of continuing pharmacy education. This activity is approved for 2.0 contact hours (0.2 CEUs) under the ACPE universal activity number 0290-0000-13-165-H04-P. The activity is available for CE credit through December 12, 2015
Contact lens wear has become a popular form of vision correction, with a variety of lenses available on the market. Regardless of the type, contact lenses generally offer many advantages over traditional eyeglasses, including better sight and peripheral vision without obstruction by frames and accumulation of condensation and/or debris on lenses.1-4
Since contact lenses move with the eyes, a more natural field of view is observed with less distortion. Contact lenses may be preferred to eyeglass options when wearers engage in sports-related or general activities.1-3
Contact lenses may also help patients overcome the perceived stigmas associated with requiring corrective lenses. The inconvenience of separate refractive eyeglasses and sunglasses may also make contact lenses more appealing. However, contact lenses are not perfect and carry their own disadvantages. Depending on the lens type, care, and handling, contact lenses may be associated with an increased risk for corneal infection.5-7
Although these factors can pose a serious risk to patients, with proper pharmacist counseling and guidance on lens handling and lens care product selection, some risks may be minimized or avoided.
According to Prevent Blindness America, more than 150 million Americans overcome visual refractive error by using corrective eyewear such as glasses or contact lenses.8
This results in an annual spending of over $15 billion on eyewear.8
It is estimated that 125 million people worldwide9
including 37 to 38 million Americans, use corrective contact lenses, contributing to the $7.1 billion and $2.4 billion markets, respectively, in 2012.10
Despite the amount of money spent on corrective eyewear, many people still experience visual problems. Approximately 21.2 million Americans 18 years and older report having some extent of vision trouble, even when wearing glasses or contact lenses.11
Fortunately, corrective eyewear can assist a substantial number of individuals. For patients 12 to 59 years of age with visual impairment, 90% to 93% of cases can be corrected with glasses or contact lenses compared with roughly 60% of patients 60 years or older.12
Approximately 84% of females and 86% of males have been identified as having correctable vision.12
Corrective lenses may be an option for many of these patients.
Although a variety of contact lenses are available for improving vision throughout the world and the United States, lenses fall into 2 main categories: soft hydrogel lenses or rigid, gas-permeable (RGP) lenses.1,3,4,13,14
Both types of lenses are used to correct vision problems such as astigmatism, hyperopia (farsightedness), myopia (nearsightedness), and presbyopia (difficulty focusing on close objects).3
Often mistakenly referred to as “hard” lenses, RGP lenses are not the same as the traditional hard lenses made of polymethylmethacrylate (PMMA), which do not allow permeability of oxygen.13,15
Even though soft and RGP lenses are made of different types of plastic, both types of lenses allow oxygen to pass through to the cornea.1,4
Decorative contact lenses that change eye color without correcting vision are also available and are used by many individuals. Similar to corrective lenses, decorative lenses are considered medical devices and are regulated by the FDA.16
Soft contact lenses are the most popular type of lens available and account for approximately 90% of lens fits throughout the world17
and 88% in the United States.10
Most commonly available as hydrogel or silicone hydrogel, soft lenses differ in plastic type and corneal oxygenation. Newer, silicone-hydrogel versions of soft lenses allow more oxygen to reach the eye compared with hydrogels.4
For hydrogel lenses, surface charge and water content are utilized for classification.14
Soft lenses are made of more flexible plastic materials compared with RGP lenses4
and contain at least 10% water.2
RGP lenses, on the other hand, are made of slightly less flexible plastic than are soft lenses and are usually replaced less often.1,4,18
Patients with astigmatisms may have better visual results with RGP lenses.13
Hybrid lenses that capture elements of both soft and rigid lenses13
and bifocal lenses19
are also available. Table 1 compares soft and rigid contact lens features.
Wearing schedules for contact lenses are based on product-specific durations of use (eg, disposable, daily or extended wear). Disposable contact lenses are worn and discarded without requiring cleaning. 21
Daily lenses are worn and cleaned on a daily basis, with replacement schedules ranging from weeks to months based on the specific product.18
Extended-wear contact lenses are available as both soft and RGP lenses that can be worn overnight, without removal, usually for 1 to 4 weeks of continuous wear.1,22
Regardless of the lens type, lens wear predisposes patients to problems such as keratitis. Keratitis is a corneal inflammation that typically presents with symptoms of eye irritation, pain, photophobia, redness, discharge, epiphora (excessively watery eyes), and blurred or decreased vision.23-26
Designated as either infectious (microbial or bacterial) or noninfectious (“sterile” infiltrates),23,27,28
keratitis may progress to more severe cases, commonly associated with microbial keratitis, and cause complications including corneal ulcers, intraocular infections, corneal perforation, and vision loss.24
Sterile and microbial keratitis may be defined in different ways based on clinical parameters and criteria. In general, both involve corneal infiltrates, but microbial keratitis presents with epithelial abnormalities such as ulcerations.28
Although rare, microbial keratitis can be associated with a variety of infective organism types, such as bacteria (eg, Pseudomonas, Staphylococcus, Streptococcus, or Serratia spp), protozoa (eg, Acanthamoeba), and fungi (eg, Fusarium).24,29-31
Of these, bacteria are more common in lens contaminations compared with a mixture of fungi, protozoa, and bacteria in contact case and solution contaminations.7
Considering the numerous risk factors that contribute to the development of keratitis, including trauma, contact lens use is considered one of the most preventable major risk factors for developing corneal infections.7,24,31-33
Many of the organisms linked to microbial keratitis can be found throughout the environment in food, water, and soil but do not readily cause corneal infection.27
It is believed that contact lens cleaning solutions and storage cases potentially introduce infective organisms to the eye while altering and/or diminishing its protective ocular defenses and ultimately exposing the eye and cornea to possible infection.5,7,27,30,31,34,35
Potential mechanisms for increased infections may be related to corneal hypoxia,6,7,27
ocular surface flora or epithelial disruption,6,7,27
altered biochemistry of protective tears, and reduced tear exchange.27
In addition, poor adherence with lens care, case cleaning,2,5,27,31
and wearing schedules, particularly extended wear through the night,20,21,27,28,36-39
contribute to an increased risk of keratitis. Considering the types of lenses and wearing schedules available, risk for microbial keratitis is greatest with extended-wear lenses, followed by daily-wear soft lenses and then daily-wear RGP lenses.6,40
Other factors, such as microbe exposure (through swimming with contact lenses)7
and smoking, may increase susceptibility to infections, while topical corticosteroid use may exacerbate them.31,41
Patient nonadherence with lens care and wearing schedules continues to be an issue among lens-wearing patients. Collins and Carney illustrated a 74% rate of nonadherence with proper use of use of cleaners, rinsing solutions, cleaning techniques, and hygiene.37
Roughly 79% of health care workers self-evaluating their contact lens care procedures reported some level of nonadherence.42
When taking into consideration hand washing before lens manipulation, correct use of an FDA-approved care system, and adherence to a daily wear schedule as elements of a adherence study conducted by Chun and Weissman, 40% of patients did not meet the standard of adherence.43
Over the past decade, reports of Acanthamoeba- and Fusarium-associated keratitis infections have been associated with contact cleaning solutions. These outbreaks have been linked to the solutions not protecting against Acanthamoeba and Fusarium spp rather than the solutions being contaminated with them. This has resulted in specific products being removed from the market. Use of multipurpose and no-rub solutions has also been considered a possible contributor to microbial outbreaks. This may be related to efficacy against specific pathogens and/ or patient nonadherence to proper lens care.5,29
Contact Lens Cleaning Accessories
Since the advent of the first soft contact lenses in 1971, cleaning solutions have evolved to provide patients with a less complex and confusing approach to contact lens care. Lens disinfection originally required patients to prepare their own saline solutions with distilled water and salt tabs to which heat was ultimately applied. These early attempts at thermal disinfection deteriorated the lenses relatively quickly, leading to infection and ocular irritation.44,45
To overcome the difficulties associated with these thermal cleaning systems, cold chemical systems were introduced, incorporating preservatives such as thimerosal, chlorhexidine derivatives, and iodine complexes. These compounds were primarily responsible for the irritation and allergic reactions experienced by patients. Thimerosal, a mercury-based compound, is noted to cause burning, stinging, and papillary hypertrophy, symptoms that mimic those of an allergic reaction, resulting in intolerance to lens wear.46
Thimerosal can also leave a gray discoloration on contact lenses due to decomposition of the mercury compound. Chlorhexidine derivatives mechanically irritate the eye by binding with mucoproteins on the lens surface, creating dry spots.44,45
Additionally, these second-generation cleaning systems required separate steps for cleaning, rinsing, soaking, and then rerinsing before reinsertion into the eye.14,45
To improve adherence and patient satisfaction, multipurpose solutions were introduced into the market in 1988, revolutionizing lens care by providing a 1-bottle care system to clean, disinfect, and rinse, all in 1 product.
The FDA testing and approval criteria help classify multipurpose solutions based on antimicrobial activity. The 3 categories of solutions are multipurpose solutions (MPSs), multipurpose disinfecting solutions (MPDSs), and no-rub solutions.47
Continued daily use of multipurpose solutions over an extended period of time can lead to bacterial contamination. Multipurpose solutions contain preservatives to maintain sterility but can also be used in higher concentrations to aid in chemical disinfection. Polyquaternium-1 (Polyquad), polyhexamethylene biguanide (PHMB), polyaminopropyl biguanide (PAPB or Dymed), and myristamidopropyl dimethylamine (Aldox) are now used as preservatives because they are infrequently associated with adverse effects.44,45
The long-chain molecular structures of these preservatives minimize buildup underneath lenses, reducing toxicity compared with thimerosal and chlorhexidine. Multipurpose solutions contain other additives to aid in cleaning and disinfecting while enhancing patient comfort. Buffering agents, such as borate, phosphate, and citrate, maintain the solution’s pH at approximately 7.4 (close to the pH of human tear film) to preserve biocompatibility with the ocular surface. Solutions are also isotonic, as changes in tonicity could inadvertently cause shrinkage or enlargement of the lens. Wetting agents (ie, Tetronic 1304, propylene glycol, and hydroxypropyl methylcellulose) are incorporated into solutions to improve comfort by mitigating dryness. By attracting and holding water, these agents retain moisture longer.45
The increased use of multipurpose solutions as 1-bottle care systems may correlate with the increasing number of disposable lens users. For patients with long replacement schedules, an enzymatic cleanser for deposit removal may be warranted. Deposition and protein accumulation can result in dryness and discomfort. It can also cause a decrease in visual acuity and the shrinking or tightening of the lens, leading to a decrease in corneal oxygenation.45,48
Enzymatic cleansers dissolve protein deposits and can be added to and used concurrently with multipurpose solutions.45
The most frequent reason for abandoning contact lens use is reported to be ocular dryness, which occurs in 13% to 22% of patients.49
Symptoms are often poorly characterized but range from discomfort and soreness to burning and irritation.49
These symptoms could be attributed to environmental factors such as smoking, pollution, and eye straining; however, the preservatives in lens care solutions should not be overlooked as potential contributors. Delayed hypersensitivity reactions may occur after prolonged use of preservatives. 46
Possible remedies include using a final saline rinse prior to lens reinsertion, changing to another formulation of multipurpose solution, or using a preservative-free product.50
Preservativefree solutions may be recommended for patients with a history of hypersensitivity and are available in a variety of multidose products. Formulations range from solutions and aerosolized cans to lens cleaning chambers and kits requiring electricity to operate. Lens wearers who use solution intermittently, such as part-time wearers, should be advised to use an aerosolized product, as bacteria cannot enter the pressurized can.44
Unfortunately, nonpreserved products are subjected to a limited shelf life of 15 to 30 days after opening, depending on manufacturer recommendation, and may be difficult to find at local retailers.
The Rub-and-Rinse Method
Although patients and practitioners alike may consider MPSs and MPDSs to be equivalent, they are not. In vitro tests demonstrate that MPDSs display antimicrobial activity in standalone tests, if soaked per the manufacturer’s recommended soaking time, compared with MPSs, which require a regimen of rub, rinse, and soak.47,51
However, as these tests are performed in vitro, MPDSs are not recommended to be used in a standalone manner. Standalone tests should not be confused with “immersion disinfection” —simply placing the lens in solution without rubbing or rinsing before soaking. No product is currently approved for immersion-only cleaning, indicating that no MPS or MPDS should be used in a soaking-only regimen. The FDA advises that all patients rub and rinse contact lenses. Table 2 reviews effective rubbing and rinsing steps.52,53
Flushing deposits off lenses with a steady stream of solution for 5 seconds should be employed before lens storage.45
Storage and disinfection of lenses should last 4 to 6 hours, depending on the type of MPDS used. As adherence to this regimen seems to be dwindling with the advent of no-rub solutions, the FDA advises patients to rinse their contact lenses before reinsertion into the eye, after soaking, to remove loose debris.54
Certain products have received the specific designation “no rub needed.” For this claim, products must demonstrate sufficient antimicrobial activity with a rinseand- soak regimen only.47
As a result, these products have eliminated the traditional, previously described, digital palm rubbing care method. The specifics of “no rub” may vary among manufacturers, but generally, each side of the lens is rinsed rather than rubbed with solution and placed into the case with enough solution to cover the lens for soaking. Again, these lenses should be rinsed before reinsertion into the eye, as per FDA recommendations, to loosen debris. Patients should be educated on the appropriate use of no-rub solutions to avoid ineffective immersiononly disinfection.51
In 2008, the FDA guidance to manufacturers of no-rub multipurpose solutions was to still emphasize the importance of rubbing and rinsing on their labeling for improved lens hygiene and safety.54
Microbes on the surface of the lens may be resistant to rinse-only methods, and rub-and-rinse regimens have been shown to be most effective in removing and killing a large number of bacteria, fungi, and amoebae.5,55-57
Although eliminating steps may be more convenient and decrease lens care time,51
re-emphasis on the digital rub technique can help mitigate the risk of ocular infection.
Contact Lens Case Care
Patients who wear reusable lenses use contact lens cases to store and disinfect lenses. Studies have indicated that lens cases are a major source of contamination with bacteria (19% to 81%), amoebae (4% to 24%), and fungi (24% to 59%), potentially leading to ocular complications.58
If not adequately disinfected, these storage cases may form biofilms that can increase the risk of infection.59
The incidence of positive contamination may be as high as 80%.7,53
This has been attributed to poor hygiene practices, as lens cases receive the least cleaning attention compared with other lens-care systems.37,60
The Contact Lens Council found that more than half of respondents to their survey did not clean their cases after each use, despite the provider’s recommendation.61
Methods of reducing lens-associated infection include patient education on decontamination and an appropriate case replacement schedule.58
Recommendations for cleaning storage cases are conflicting.53
Individual manufacturers of multipurpose solutions and the FDA provide guidance to specifically address the storage and cleaning of cases. Recommendations vary with regard to rinsing agent, air-dry position, and replacement schedule.
Most manufacturers recommend the use of their own solution to disinfect and rinse their branded cases. Although this information is readily available in product inserts, the rinsing of cases with tap water has become a common practice among wearers,58 with even 36% of optometrists recommending water rinses.53
This has been linked to a variety of infections, so avoidance of this practice should be emphasized.52
Other patient-perceived methods of disinfection include microwaving or boiling of cases. Cases may not withstand these harsh temperatures, resulting in distortion of the plastic; therefore, such methods are not recommended. Manual disinfection with items such as cotton buds or toothbrushes should also be avoided because of concerns about potential residue and bacteria associated with toothbrushes.53
Any solution remaining in the case after disinfection and storage should be discarded, as the reuse of solutions can be a significant risk factor for case contamination.58
With increasing options for eye care (brand and generics), patients may purchase various solutions, depending on personal preference, physician recommendation, and cost. Unfortunately, this may lead to the mixing of different multipurpose solutions, even in the same case, which can cause discoloration or clouding of the lens.45
Multipurpose solutions should be switched concurrently with a new pair of lenses. “Topping off” is the custom of adding new solution to old or remaining solution in a case. Inadequate disinfection of lenses can occur if solutions are mixed in this fashion. Additionally, during topping off, the tip of the bottle may be immersed into the old solution, causing a back flow and contamination of the new solution.7
The warning against this practice is printed on product labels and package inserts.
After appropriate rinsing, it is recommended that the lens case be air dried. The FDA suggests flipping the lens case over face down, while most product recommendations do not specify a method. It has been argued, however, that inversion of lens cases may result in incomplete drying, leaving a medium for bacterial growth. For patients who primarily care for their lenses in the bathroom, contamination from toilet environmental bacteria can disseminate after toilet flushes and settle on surfaces,58,62
potentially infecting cases. For these patients, it may be prudent to recommend the inversion of their cases during drying.
Frequent case replacement is recommended as another measure to help reduce ocular infection. More than one-half of patients report not replacing their cases frequently, with 14% of US patients never replacing their lens cases.63
All contact lens users should be encouraged to replace their cases often. Even part-time wearers who replace solutions infrequently and leave cases unopened for an extended period of time should be educated.58
The most recent FDA advice is to replace cases every 3 to 6 months.52
The implementation of replacement reminders may help improve adherence. Calendars and appointment schedules can serve as useful tools. Commercial electronic reminders are available to help track lens and case replacement schedules with a simple countdown setting for 30, 60, or 90 days.64
Other electronic and cellular device applications are available for friendly e-mail reminders for lens change.65
As a rule of thumb, each new bottle of solution gets a new lens case. Cases that are cracked or broken should also be replaced as soon as possible.
Discard Versus Expiration Date
The FDA recommends that manufacturers include both the discard and expiration dates to help contact lens wearers identify expired products.52
The expiration date is traditionally defined as the date at which a product is no longer expected to be fresh or effective. After a product is opened, the discard date indicates when any remaining solution should be discarded, as the risk of contamination increases the longer a bottle has been open.66
Individual products should be referenced for their particular discard and expiration dates, and consumers should be educated to never use products beyond these printed dates.
As studies have shown that nonadherence is still an issue, even after years of contact lens wear,37,43
patient education continues to be a fundamental component of improving adherence and ensuring success with lens care systems.45
Pharmacists may be involved in initiating, selecting, and monitoring therapy to help improve adherence and prevent potential side effects, but pharmacists can also play a key role in patient education. The provision of pharmaceutical care and pharmacist patient education can achieve outcomes associated with improvements in quality of life.2,67
Considerations in patient education should include the method of delivery and the dissemination of accurate information. Table 3 identifies general tactics to incorporate into counseling sessions when assisting patients in the use and care of their contact lenses.68
There are no predictable patient characteristics to identify nonadherent patients, as nonadherence can be attributed to many factors, including age, education, and wearing schedule.68
Eighty-seven percent of eye care practitioners identify specific brands when recommending contact lens care systems to patients,10
but 44% of patients do not follow their health care provider’s advice.68
These gaps in care, combined with patient risks for nonadherence, are excellent opportunities for pharmacists to educate all patients on the risks and benefits associated with lens care procedures. As accessible health care practitioners, pharmacists are readily available to assist patients in lens care product selection and overall understanding of eye care.
The following patient education points regarding contact lens care are vital to minimizing ocular infections and enhancing contact lens performance. Pharmacists may consider incorporating these items into discussions with their patients regarding lens care:
Contact Lens Solutions
Before handling contact lenses, wash hands with soap and water and then dry them.52,69
Dispose of lenses according to the recommended replacement schedule (eg, daily, weekly, monthly).68,70
Rub and rinse lenses, as directed, for added cleaning and disinfection effectiveness regardless of product type (ie, rub or no-rub variety).2,52,69,71
Avoid sleeping with lenses in, unless the product is approved for this.70
Avoid smoking while wearing contact lenses, as this may cause irritation and is associated with more complications than in nonsmokers.70
Remove lenses before swimming or before entering swimming pools, hot tubs, or natural water sources, as this may increase the risk for infections.69,70
If eyes become red or irritated or blurry vision occurs, remove lenses immediately and seek professional advice.2,52
Have a backup pair of eyeglasses available in case of contact lens problems.70
Check with your pharmacist or eye care professional before using topical eye care products. Contact lenses may need to be removed before instillation, as preservatives may irritate the eye.70
Aerosol products, such as hairspray, cologne, or perfume, should be applied before lens insertion.70
Only purchase contact lenses, including cosmetic or decorative lenses, with a prescription from authorized vendors.70
Contact Lens Storage Cases
Use solutions within the provided expiration and discard dates.2,52
Discard remaining solution after each use. Do not top off or reuse leftover solution in the case.2,52,71
Avoid exposing contact lenses to water (eg, tap, distilled, bottled), as this may increase the risk of infection.2,52
Avoid nonsterile solutions, such as saliva, for wetting or disinfecting.2,52
Avoid using rewetting drops or saline solutions to disinfect contact lenses, as they are not approved or considered effective for this use.71
Avoid surface contact with the solution bottle tip and keep the bottle tightly sealed when not in use.
Clean, rinse, and air dry the case at each lens removal.52,71
Consider inverting the case while air drying.52,71
Replace the case every 3 to 6 months, or as directed.52,71
Follow up with an eye-care specialist for regular examinations.68,70
If eye irritation occurs (eg, pain, redness, blurred vision, light sensitivity, excessive tearing, feeling something in the eye), consult an eye care professional.2,71
Successful contact lens use depends on patient adherence to wearing schedules and lens care procedures, in addition to regular visits to ophthalmic care providers. Pharmacists can play a pivotal role in this success by serving as an information resource to promote appropriate contact lens wear, care, and storage. In addition, pharmacists can help identify and select contact lens care products that meet patient needs and improve adherence while minimizing ocular risks such as infection or damage.
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