contact lens care
Two New MPS Products that Deserve a Closer Look
BY MICHAEL A. WARD, MMSC, FAAO
These are exciting times in the contact lens care market. The newest contact lens care products feature moisture-enhancing characteristics and offer improved patient comfort and convenience. Two new multipurpose solution (MPS) products made their debut in the fourth quarter of 2004: ReNu with Moisture Loc (Bausch & Lomb) and Aquify 5 Minute Multi-purpose Solution (CIBA Vision). I'll explain why they deserve a closer look.
ReNu with MoistureLoc
This product is the latest generation of B&L's ReNu MPS line, replacing ReNu MultiPlus. B&L has significantly changed its formulation with ReNu with MoistureLoc by using a different preservative and enhancing its demulcent/lubrication properties.
The new formulation also contains polyquaternium-10, which is new to the MPS market. It's a cellulose-based cationic polymeric conditioner that acts to retain moisture. Don't confuse polyquaternium-10 with Alcon's disinfectant polyquaternium-1 (Polyquad).
ReNu with MoistureLoc also contains the surfactant poloxamer 407, which works with Hydranate (a sequestering agent/protein remover) to prevent protein and debris deposition on the lens surfaces. B&L has removed EDTA and polyhexamethylene biguanide (PHMB) from the MoistureLoc formulation and has replaced these preservatives with alexidine in a 0.00045% concentration. Alexidine is a relatively small-molecule biguanide with a long history of use in oral hygiene products.
Aquify 5 Minute MPS
This product is another new entrant to the U.S. MPS market. (It's branded as SoloCare Aqua outside the United States.)
As a testament to the efficacy of digital cleaning, Aquify MPS has approval for quick disinfection if patients follow the "rub and rinse" instructions, which include a 10-second rub, then a five-minute soak. For patients who omit the rubbing step, the product has approval for four-hour, no-rub disinfection for all soft contact lenses, although patients must still properly rinse the lenses.
Aquify MPS contains 0.0001% polyhexanide (PHMB) and EDTA as preservatives. It features CIBA's HydroLock formulation, which includes Dexpant-5 (dexpanthenol). Dexpanthenol (pantothenyl alcohol) binds water and acts as a barrier to evaporative drying. Dexpant-5 works in conjunction with humectant-acting sorbitol (a naturally occurring hexahydric alcohol) to keep lenses moist.
Note that for all no-rub labeled MPS products, patients must perform a significant rinsing step (usually five seconds per side per lens) to ensure proper disinfection.
Striving for Dryness Relief
New contact lens care product development has clearly emphasized alleviating moisture-related issues including end-of-the-day dryness symptoms. This is an important industry-wide mission because dryness-related discomfort accounts for a significant number of contact lens drop outs each year. The new MPS products introduced in 2004 will benefit our patients for years to come.
Mr. Ward is an instructor in ophthalmology at Emory University School of Medicine and is director, Emory Contact Lens Service.