contact lens care
An Ignored Warning Label Leads to Ocular Surface Toxicity
Patient VN is a 21-year-old female with a history of successful soft contact lens wear since age 15. She presented with complaints of gradually worsening mild redness and burning, OS>OD, for the last four months, for the last four months. Her symptoms were worse in the morning and late in the day. She denied itching, pain or discharge. Slit lamp evaluation revealed a generalized 1+ conjunctival injection with diffuse fine corneal staining and associated mild ciliary injection (Figure 1).
Her current lens type is a biweekly HEMA toric hydrogel. She uses the Clear Care (CIBA Vision) peroxide system as her daily disinfectant. She further reported using get the red out drops. Specifically, she was using Visine LR (Pfizer) eye drops two to three times a day with the starting date roughly coincident with her onset of symptoms.
The presumptive diagnosis was ocular surface toxicity. We instructed her to discontinue contact lens wear and other eye drops and to use only preservative-free artificial tears. She was to use nothing else in her eyes and she was scheduled for follow up in one week.
We re-examined VN one week later and noted marked subjective improvement. Her ocular surface had cleared except for some residual redness. She returned to lens wear with new lenses and the same care system. Her eyes were clear without inflammation at the one month visit.
The above example illustrates how simply and innocently a contact lens wearer may use a product not intended for use with contact lenses that results in an inflammatory reaction. This is a problem with preserved artificial tears as well. The difference here is the vasodilatation as a rebound effect of chronic vasoconstrictor use.
The Visine LR product label revealed the active ingredient to be Oxymetazoline HCL 0.025% with inactive ingredients listed as benzalkonium chloride, boric acid, edetate disodium, purified water, sodium borate and sodium chloride. This product is not labeled for use with contact lenses.
Although this and similar products have warning labels against use with contact lenses, lens wearers seldom read them. The two ingredients most likely to cause an adverse effect are Oxymetazoline and benzalkonium chloride (BAK).
Oxymetazoline HCL is an α-adrenergic agonist that causes potent vasoconstriction and is a long-acting ocular decongestant. Ocular decongestant effectiveness tends to decrease over time, which may encourage its overuse.
BAK binds to and is concentrated in soft lens polymers; later release onto the ocular surface causes a toxic event. BAK interferes with cellular mitosis, slows epithelial healing and can cause a toxic keratitis when used over hydrogel lenses. Cytotoxicity is dose-related; greater doses result in greater toxicity. All BAK-preserved eye drops are contraindicated with soft contact lens wear.
Caution Your Patients
You should regularly question your patients regarding their lens care practices and caution them not to deviate from your instructions or change brands without first checking with your office.
Mr. Ward is an instructor in ophthalmology at Emory University School of Medicine and Director, Emory Contact Lens Service.