SPECIAL REPORT

A Stepped Approach to Ocular Allergy

By Uday Devgan, MD

The characteristic itchy eyes experienced in patients with ocular allergies are common and can be very disruptive to patients. That maddening itch not only makes them miserable, but it also has the potential to compromise the ocular surface, make contact lens wear difficult or impossible and interfere with planned eye surgery.

Patients with ocular allergies almost always complain of itching, but they might have other symptoms as well, such as irritation, watering, light sensitivity and redness. If surgery is planned, then we need to quiet the eye first to help smooth the way for a successful, comfortable healing process. But even when surgery isn't on the schedule, we should make patients comfortable by easing frustrating allergy symptoms.

Stepped Treatment

For ocular allergies, most doctors choose a stepped approach to treatment. We start off with the simplest treatment with the fewest side effects, and then gradually step up to different classes of medications as needed until the patient experiences relief. I follow these steps:

1. Avoidance. I couldn't breathe clearly through my nose until I went to college. Why? Because my sisters had cats. Needless to say, as an adult, I don't have a cat because I want to avoid the cat dander allergens. I always advise my patients to start by avoiding the allergen. It might mean giving the kitty to a cousin. If it's an environmental allergen such as pollen, then I advise patients to spend less time outside on high pollen count days, wear sunglasses outside, dust and vacuum frequently and use artificial tears to wash the allergen off the ocular surface. Avoiding the allergen is the best advice you can give to patients.

2. Topical antihistamines. If avoidance isn't possible or doesn't relieve symptoms, the next level of treatment is a topical antihistamine. In addition, because most patients are unable or unwilling to avoid the allergens, starting them on an antihistamine drop right away is a reasonable choice.

Of the multiple inflammatory pathways involved in ocular allergies, topical antihistamines block one (the histamine pathway). This helps, but these antihistamines certainly do not stop 100% of the inflammation. Common drops include bepotastine besilate ophthalmic solution 1.5% (Bepreve, Ista), olopatadine hydrochloride ophthalmic solution 0.1% (Patanol, Alcon), ketotifen 0.025% (Alaway, Bausch + Lomb) and alcaftadine ophthalmic solution 0.25% (Lastacaft, Allergan).

3. NSAIDs. Nonsteroidal anti-inflammatory drugs (NSAIDs) stabilize mast cells, which can release inflammatory mediators, thus inhibiting a pathway of inflammation. In the eye, allergies were the first indication for this class of drugs. When it comes to selecting an NSAID, the main difference between the available products is the duration of action. Some drops are used 3 or 4 times a day, but it's far more convenient for patients to use them only once or twice per day.

Ketorolac tromethamine ophthalmic solution 0.5% (Acular, Allergan) is indicated for allergies, but patients need to use the drops four times per day. That can pose issues with compliance, especially because any drop they take three or more times per day has to go to work with them.

In some situations, ophthalmologists may recommend NSAID treatment first if the patient's symptoms and clinical signs warrant this approach. While ketorolac tromethamine 0.5% is the only NSAID indicated for allergies, doctors often prescribe other NSAIDs such as bromfenac 0.9% (Bromday, Ista) once per day or nepafanac 0.1% (Nevanac, Alcon) three times per day to increase compliance and efficacy.

4. Steroids. For severe allergies whose symptoms can't be resolved using NSAIDs, I consider adding a steroid. Steroids block inflammation on many pathways, quieting the eye quickly and effectively. Some steroids are indicated for inflammation, while others are specifically indicated for allergies.

Prednisolone acetate ophthalmic suspension 1% (Pred Forte, Allergan) is a strong weapon against ocular inflammation but its side effects include induced cataract changes and glaucoma, especially with long-term use. Loteprednol etabonate ophthalmic suspension 0.2% (Alrex, Bausch + Lomb) is specifically indicated for ocular allergies. It has a steroid effect with an easier side effect profile due to its ester configuration, which tends to have a better safety profile than ketone-based steroids. Because of the risks, any type of steroid should be limited to short-term use.

5. Systemic medications. In some circumstances, it may be beneficial to add a systemic medication to treat the allergies. The most commonly prescribed class of medicines for this purpose is the antihistamine group, many of which are now available over the counter. In rare situations, systemic steroids can be used to further suppress the immune response of allergies.

Adjustments and Additions

The stepped approach to treating ocular allergies isn't a stand-alone system. Not only may patients require an individualized approach in terms of drug choice, but they may also have complex cases with multiple problems at work on the ocular surface or systemically. Therefore, any of the following tasks may be required:

• Make adjustments. Of course, patients respond differently to medications. I explain to my patients that the painkiller they like to use for a headache might not work for me, and the same is true of other classes of medications. That's why if one drug doesn't work the way we'd like, I'll switch patients to a similar drug from the same class or perhaps to a new type of drug. In some cases, it's a challenge to find the right drug for a patient, but it's worth the time to figure out which medication works best before giving up and moving up the ladder to a drug with a more serious side effect profile.

• Address systemic allergies. An oral medication may be used as part of ocular allergy treatment, as discussed above. But it's important for us to question patients about the full range of other allergy symptoms, such as sneezing or a runny nose. If symptoms of systemic allergies are bothering patients, then we should prescribe an oral antihistamine or, in rare or severe cases, an oral steroid.

• Diagnose and treat other ocular surface problems. When patients have ocular allergies, we sometimes find that this isn't the only problem compromising the ocular surface. Meibomian gland dysfunction and blepharitis are possible (Figure 1). Patients may have chronic dry eye. Dry eye also may be caused by the allergic condition, since the spectrum of allergic activity, ranging from mild to severe, can destabilize the tear film and cause dry eye. Another problem associated with bad allergies is chemosis, which we can usually treat with steroids.

Figure 1. A patient presenting with a case of blepharitis.

Figure 2. Patient presenting with a case of allergic conjunctivitis.

New Options

Whether I'm discussing the challenges of treating complex allergy cases or just talking to patients about their frustration with allergy eyes, I like to add a reminder about the future of ocular allergy medications. Allergies don't typically go away, so patients who use allergy drops will probably need to use them for many years. For that reason, we want to find a medication that is efficacious for the patient and has an acceptable safety profile. Ocular allergy treatment will continue to become more effective and convenient as new drugs are developed. ■