Treating Ocular Irritation

Making patients more comfortable with the proper medication

By David Goldman, MD

When answering the question, "Who do I treat for ocular irritation?" I answer that I treat patients who are either symptomatic or undergoing some sort of procedure.

First Steps

Treating a patient with ocular irritation begins with obtaining their ocular history. This includes learning about their chief complaints, specifically exacerbating factors. It's also important to uncover whether this is something constant or if it waxes and wanes. For example, many of our allergy patients come in fully aware of their allergies. What complicates the situation is when they're already taking something, such as an oral antihistamine that makes their eyes dry.

When performing an exam, we're looking at tear film breakup time (TFBUT) and any sign of staining, not just of the cornea but of the conjunctiva as well. I think lissamine green is an excellent stain to help evaluate the tear film, but you can also use rose bengal or fluorescein. In addition to the quality and quantity of the tear film, we also have to look at the puncta to determine if it's open or stenotic. Some patients complain of tearing that hasn't improved with dry eye therapy and what they really have is punctal stenosis. Dryness was never really an issue.

I think we're really starting to focus more on the lid margin itself and realizing the importance of the meibomian gland secretion and its contribution to a healthy tear film. In the past, we focused on using the Schirmer's test for determining if a patient was producing enough aqueous tear. But now we're considering and evaluating the other components of the tear as well, such as the lipid layer. Not only does a patient need to produce enough quantity of tears, but that tear quality needs to be sufficient to remain on the ocular surface as well in order to sustain good vision and comfort.

Treatment Options

Often patients come to me because they've already attempted and failed multiple regimens. Even if some of the medications they've tried may be appropriate, I often start with something different because patients tend to be more compliant when beginning a new medication.

In general, my selection depends on the patient's condition. For a patient with very mild dysfunctional tear syndrome who is just using the occasional artificial tears and isn't too bothered by discomfort, or for someone who has an acute flare-up because of an allergy, I recommend medications such as olopatadine (Patanol, Alcon), olopatadine (Pataday, Alcon) or ketotifen (Zaditor, Novartis) — all are good for the allergic component. I've also found some newer artificial tears that are focusing on patients with meibomian gland disease — specifically Systane Balance (Alcon) and, to a lesser extent, Soothe XP (Bausch + Lomb), both of which have more of a lipid component to them — to be more effective for many patients. I prefer the Systane Balance because it's a more consistent emulsion and has much less blur profile than Soothe XP.

Data thus far shows that Systane Balance not only helps improve the volume of the tear film but also improves TFBUT for at least 2 hours. I think by helping to establish a good tear film, Systane Balance will help patients with discomfort and provide better vision.

Some patients with a more advanced problem need something stronger. For example, a patient who is using drops all day long, every day, isn't someone I think will respond to artificial tears, so I consider medications such as cyclosporine (Restasis, Allergan). If the patient is acutely or badly inflamed, I'll use a combination antibiotic/steroid such as a tobramycin (TobraDex, Alcon) or loteprednol and tobramycin (Zylet, Bausch + Lomb), which not only provides comfort by decreasing inflammation but also decreases the bacterial overgrowth, which I think is another inciting factor of OSD.

I'm looking forward to the newer formulation of tobramycin/dexamethasone (TobraDex ST, Alcon), which should be available soon and have overall lower concentrations of steroid and antibiotic, but still get the same level of medication to the tissues.

If I've started a patient on tobramycin and dexamethasone or loteprednol and tobramycin, I see them again after 1 or 2 weeks to reassess how comfortable he is and to ensure there are no side effects from the medication. If a patient is only on the drop for 5 to 7 days, I won't bring him back for the recheck because I find the time it takes for him to develop a steroid response has already passed. My goal with medications that have steroid components really is to get the patient comfortable and the inflammation under control so I can transition him to a more long-term therapy.

I also recommend traditional non-prescription therapies to my patients with severe dry eye or meibomian gland disease such as warm compresses and ensuring that their lids are closed at night. I'll recommend lid scrubs or baby shampoo, but only to patients who have significant debris in their lashes. Otherwise, baby shampoo can cause even greater disruption to the tear film and worsen irritation.

Inflamed lid margin with inspissated meibomian gland and lid telangiectasias.

Treating Allergy

With allergy, you must try to remove the offending allergen, if possible. In true allergy, the treatment is more about trying to prevent the inflammatory cascade by stabilizing the mast cells. Patients I see that are already on loratadine (Claritin, Schering-Plough) or cetirizine (Zyrtec, McNeil-PPC) already have extremely dry eyes. They have a combination of allergy and dry eye. I typically will start them with a steroid to get them comfortable again and then transition them to therapy aimed at what the underlying cause is. If it's allergy, I recommend a Patanol or Pataday type of drug. If it's dry eye, I may start with an artificial tear. If a patient is using tears all day long, I'll recommend Restasis. That said, I've been very impressed with the performance of Systane Balance. My patients who have tried it have noticed a significant improvement in their ocular comfort.

Benefits of Going BAK-Free

Benzalkonium chloride (BAK) is the most commonly used preservative in drops for the eye. Recently, physicians have become more aware of the downsides of using it. Occasionally, used in low concentrations, I don't think it poses a problem. However, in chronic use, such as glaucoma medications where the patient is using multiple drops several times a day, it may cause significant disruption of the tear film and decreasing TFBUT.

Healthy TFBUT is approximately 8-10 seconds, which coincides with the eye blinking every 8-10 seconds. So, if the eye is blinking every 8-10 seconds but the tear film is breaking up every 5 seconds that's 3-5 seconds where the cornea is exposed and inflammation is occurring. If this goes on for a long time, you can see significant deterioration of the ocular surface.

Being Proactive

Age plays a role in treatment as well. If you look at a cross-section of 20- to 30-year-old patients coming in for LASIK, a very small percentage have meibomian gland disease. Their problem post-LASIK is going to be more of a neurotropic cornea. They may do better with a preservative-free artificial tear that's placed in the eye more frequently. If you're looking at an 80- year-old patient, about 80% of those patients have meibomian gland disease and will benefit from a drop that supplements the lipid layer.

For an older patient, if they're about to undergo cataract surgery, and have significant meibomian gland disease, I want to get it under control prior to cataract surgery. I do this for multiple reasons; I get better topography and IOL readings and it provides better postoperative comfort. In general, I use TobraDex, because it's one prescription and has both antibacterial and anti-inflammatory properties.

Ultimately, compliance is the biggest issue. You need to educate your patients about why they have the symptoms they do and why you're recommending a specific therapy. As long as they're compliant, you'll have a happy patient.

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David A. Goldman, MD, is Assistant Professor of Clinical Ophthalmology of the Bascom Palmer Eye Institute in Palm Beach Gardens, Florida. Dr. Goldman is a consultant to Alcon, Allergan, and Aton Pharma.