What Is New and Effective for Treating Ocular Allergies

What Is New and Effective for Treating Ocular Allergies

What Is New and Effective for Treating Ocular Allergies

 A 0.2%  olopatadine hydrochloride drop and potent over-the-counter antihistamines can benefit ocular allergy sufferers.

Michael Raizman, MD

Although ocular allergy may not be our patients’ chief complaint, many of them suffer significantly from ocular allergies. In my practice, only a handful come in specifically to be treated for ocular allergy, but as many as 40% of my patients will have allergy symptoms that affect their eyes at some time. If we are to help these patients, we need to be proactive and ask them about symptoms, even at times of the year when they are asymptomatic.
 
Most ocular allergy patients self-medicate, but, unfortunately, most choose drops that are either ineffective or worse. It is worth the effort to counsel patients about effective means to reduce allergy symptoms.

New Solution
    
Two recent advances in treatment of ocular allergy are worthy of note: the introduction of a 0.2% olopatadine drop (Pataday™ Ophthalmic Solution; Alcon) and the over-the-counter (OTC) availability of topical ketotifen drops (Zaditor®, Novartis; Alaway®, Bausch & Lomb). These medications, along with a few smart environmental modifications and simple palliative measures, can help keep most patients comfortable and symptom-free during allergy season.
   
Pataday is a  double-strength version of the widely accepted Patanol® (olopatadine 0.1%; Alcon). The higher concentration confers two useful benefits. The first is more convenient dosing. With effects that last more than 12 hours, Pataday can be taken once in the morning and not have to be taken again during the day. This once-a-day dosing is especially convenient for children, who may dislike or even resist having drops put in their eyes, and contact lens wearers, who must take their contact lenses out to instill drops.
   
A second benefit is that the higher olopatadine concentration makes Pataday a more effective solution. I find that my patients get faster, more complete symptom relief with Pataday than they did with Patanol (and Patanol is quite effective).
    
While Pataday drops are designed and labeled for once-a-day dosing,  olopatadine, like other members of its class, is very safe and can be used more often if necessary. I start my patients off with one drop a day but give them permission to use more on days when symptoms are very bad.

Allergy vs. Dry Eye
   
However, I also make sure to counsel my patients that, even though they have allergies, not all ocular irritation is histamine-mediated. Many individuals will experience irritation, burning, and even a little itching in their eyes in the afternoon, particularly if they work on a computer all day. While allergy patients may naturally want to reach for their allergy drops, I suggest they try artificial tears. Even though the allergy drop feels good on the eye, artificial tears can have the same effect because irritation in the afternoon is often caused by ocular dryness, a reaction that isn’t histamine-mediated. Using a good artificial tear preparation can be an easy, effective, and inexpensive way to get relief between doses of a medicated allergy drop.

Easy Access
   
The OTC availability of previously prescription-only ketotifen drops is making it easier and less expensive for patients who don’t make it to their doctors’ offices to get an effective product to treat allergies. The fact that ketotifen is now off patent also lowers its cost. The ketotifen in Zaditor and Alaway is a potent antihistamine that blocks histamine responses in the eye and decreases symptoms like itching, burning, and irritation.
   
Prior to the OTC availability of these drops, the antihistamine/vasoconstrictor combinations that were (and are) available without a prescription were not much better (and maybe even worse) than placebo. The efficacy of the antihistamine in these combination products is much lower than that found in Zaditor and Alaway. Additionally, the vasoconstrictors in these products can produce rebound hyperemia and tachyphylaxis.
   
As a result, patients who use products with vasoconstrictors may end up instilling the drops at shorter and shorter intervals, ultimately ending up with eyes that are redder than before they started using the drops. Therefore, it is a genuine benefit to patients who self-medicate to be able to go the drugstore and get an effective OTC antihistamine drop that doesn’t contain a vasoconstrictor.

Back to Basics
   
While medications are important in the treatment of ocular allergies, making some basic behavior and environmental modifications can also go a long way toward preventing or reducing symptom formation. My number one rule for patients is: Don’t rub your eyes, even if they are itchy or bothersome. Rubbing causes blood vessels to dilate and mast cells to degranulate and release a mix of histamine and inflammatory mediators onto the ocular surface, making the situation worse. Offer patients better means to obtain relief from itching.
   
It can also help to avoid allergy triggers, as much as possible. Those triggers may be pollen, pet hair, dust mites, or a combination. While avoiding them may seem obvious, patients with allergies often don’t put this piece of advice into practice unless their eye doctor spells out specific actions that will help. Patients should wash their face and hands every time they encounter the allergen, and if possible, also brush their hair when they come indoors. People who are sensitive to outdoor allergens like pollen should drive with the windows closed with their vents on recirculate or the air conditioner on. Bedroom windows should stay closed too, even on warm nights. An air conditioner will cool the room and filter the air. People who are allergic to dust mite proteins should also outfit their bedrooms with pillow and mattress covers that don’t allow dust mites to pass through.
   
Additionally, allergic individuals should not allow pets in their bedrooms, much less on their beds. Pets not only produce allergens, they pick up and carry significant quantities of other allergens, like pollen, in their fur. Human hair, especially long hair and hair coated with styling products, can also pick up and hold allergens. Allergists often recommend washing hair before going to bed to avoid sleeping in what can literally be a nest of allergens.
   
Finding Relief
    
Patients may be able to prevent recurring seasonal allergy symptoms by starting on an antihistamine/mast cell stabilizer drop a few weeks before their allergy season typically begins. In addition to olopatadine, drugs in this class include epinastine (Elestat®; Inspire Pharmaceuticals), ketotifen, and azelastine (Optivar®; Meda Pharmaceuticals), although some patients complain that azelastine produces an unpleasant taste in their mouth.
   
For symptoms that can’t be prevented, simple palliative measures include chilled artificial tears, ice packs, and cold compresses over the eye. Cooling reduces itching and other unpleasant sensations, making cool compresses or drops a much better alternative than rubbing. Cold artificial tears are not only soothing; they also serve to wash allergens and histamine out of the eye.
   
Most patients who wear contact lenses can tolerate them during allergy season, but if regular lenses are uncomfortable, switching to a daily disposable lens for the duration of the allergy season can help. Daily disposable contact lenses minimize the allergen load that can build up on lenses and therefore decrease symptoms.
    
If patients make smart behavioral and environmental modifications, and use a good antihistamine/mast cell stabilizer drop, most will find relief from mild to moderate seasonal or perennial allergies. Steroids are rarely necessary in the treatment of allergies, but for patients who can’t get relief from other therapies, loteprednol etabonate 0.2% (Alrex®; Bausch & Lomb) is generally safe and effective.

THE BOTTOM LINE
 
Allergy is a highly prevalent cause of ocular discomfort. Recent advances in treatment include the introduction of Pataday ( olopatadine 0.2%), which offers once-a-day dosing and excellent allergy relief. The OTC availability of ketotifen (Zaditor and Alaway) provides a non-prescription option that is strong enough to block symptoms and doesn’t contain a vasoconstrictor. In addition to medications, some simple behavioral and environmental modifications can help patients prevent or reduce allergy symptoms. Patients often just need reminders from their providers about which modifications to make and why they are important.

Michael Raizman, MD, practices at Ophthalmic Consultants of Boston and is associate professor of ophthalmology at Tufts University School of Medicine in Boston, MA.