Treatment and Management of Allergic Conjunctivitis

By Rajesh K. Rajpal, MD; Christine Burris Wisecarver, OD; and Dawn Williams

Allergic conjunctivitis is estimated to affect 20% to 40% of the US population.1 It is a type 1 hypersensitivity response of the immune system to allergens, either inherent or acquired from the environment. Of specific interest in allergic conjunctivitis is the response of mast cells to allergens. Immunoglobulins on the surface of the mast cell cause the cell to degranulate once sensitized, thereby releasing a variety of proinflammatory mediators.2 Histamine, one of these mediators, is responsible for increased vessel permeability, vasodilation, and increased mucosal secretion.

Allergic conjunctivitis can present as a seasonal disturbance caused by triggers such as pollen or mold, or it may be a chronic illness occurring in response to common environmental factors like pet dander, dust, or foods. In either case, patients will present with specific symptoms: ocular itching (the hallmark of allergic conjunctivitis), tearing, rhinitis, postnasal drip, and sinus congestion.3 These symptoms are most often bilateral in nature. Signs may include conjunctival hyperemia, chemosis, fine papillae, and edematous eyelids (perhaps severe enough to cause pseudoptosis).

Because allergic conjunctivitis can present in varying degrees of severity, treatment may range from topical over-the-counter (OTC) therapies to stronger, prescribed modalities. Bielory and others have proposed a hierarchial approach to treatment and management.4 This article outlines a four-step method, with the goal of using the least-invasive medications to reduce the patient's symptoms and their recurrence.

MILD ALLERGIC CONJUNCTIVITIS

The treatment of patients with mild or intermittent allergies should be focused on identifying the underlying triggers and taking steps to avoid them. Eye care specialists should also ensure that any coexisting disease (ie, blepharitis, rosacea, dry eye) has been identified and treated, as this may exacerbate the allergic response. Patients may benefit from the short-term use of topical OTC vasoconstrictors such as Vasocon (Novartis) or Naphcon-A (Alcon Laboratories, Inc.). In addition, cold preservative- free artificial tears, cold compresses, and the frequent replacement of contact lenses (preferably 1-day disposables) are recommended. Eye rubbing should be firmly discouraged to prevent any mechanical disruption of the mast cells.

MODERATE ALLERGIC CONJUNCTIVITIS

In addition to the steps mentioned previously, patients with moderate conjunctivitis typically need a topical combination medication that has both an antihistamine and mast cell stabilizing mechanism of action. A variety of OTC formulations of ketotifen fumarate 0.025% are now available (eg, Alaway [Bausch + Lomb], Claritin Eye [Schering-Plough HealthCare Products Inc.], Refresh Eye Itch Relief [Allergan, Inc.], and Zaditor [Novartis]). They can be used in pediatric patients 3 years of age and older.

Prescription antihistamine-mast cell stabilizing agents are also highly effective. Approved in 2004, Pataday (olopatadine HCl 0.2%; Alcon Laboratories, Inc.) is a once daily topical antihistamine-mast cell stabilizer. It may be used in patients aged 3 years and older and is a pregnancy category C drug. Approved in 2009, Bepreve (bepotastine besilate 1.5%; Ista Pharmaceuticals, Inc.) is another topical antihistamine/mast cell stabilizer used to treat allergic conjunctivitis. It is also a pregnancy category C drug, however, approved for use in patients aged 2 years and older.

The latest drug to join this class of medications is Lastacaft (alcaftadine ophthalmic solution 0.25%; Allergan, Inc.). Lastacaft is expected to behave similarly to Pataday and Bepreve, but FDA clinical trials found relief from ocular itching as early as 3 minutes after instillation, with benefits lasting up to 16 hours.5 Lastacaft is a pregnancy category B medication and may be used in pediatric patients aged 2 years and older. It is the only medication in its class to be FDA labeled for the prevention of itching, so seasonal therapy administered early may give patients the greatest symptomatic relief.

SEVERE ALLERGIC CONJUNCTIVITIS

Moderate Severity

In severe cases of conjunctivitis, topical antihistamines may have little effect on the patient's comfort. Short bursts of a topical steroid should be introduced to the treatment regimen. Alrex, Lotemax (both from Bausch + Lomb), and Pred Forte (Allergan, Inc.) are all viable options that will quell inflammation and offer relief. Because there are known risks associated with the long-term use of topical steroids, it is wise to select the lowest dosing schedule and concentration that will improve the patient's symptoms.

Restasis (cyclosporine ophthalmic emulsion 0.05%; Allergan, Inc.) may also be helpful at this stage as a topical immunosuppressant. Although the drug's exact mechanism of action in relieving symptoms may be unknown, improved comfort may be due to the increase in tear production and/or decrease in inflammation of the ocular surface. Restasis is a pregnancy class C medication; its safety has not been established in children under the age of 16.

It is important for eye care specialists to be cognizant that coexisting allergic symptoms such as allergic rhinitis need to be managed as well. In these circumstances, oral antihistamines such as Benadryl (McNeil Consumer Healthcare), Claritin (Schering-Plough HealthCare Products Inc.), Zyrtec (McNeil Consumer Healthcare), or Allegra (Chattam, Inc.) should be utilized.

Furthermore, studies have also shown that nasal corticosteroids can effectively relieve ocular allergy symptoms. Flonase (GlaxoSmithKline), Nasonex (Schering Corp.), and Veramyst (GlaxoSmithKline) are often used to treat concomitant rhinitis or sinus congestion.

High Severity

For chronically atopic patients not relieved with topical therapies and oral antihistamines, oral steroids may be necessary. Comanagement with an allergistimmunologist is usually necessary at this stage due to the patient's complex systemic condition.

SUMMARY

With the myriad options available for the treatment of allergic conjunctivitis, selecting initial therapy can be daunting. Furthermore, patients' variable responses to medications can make the condition frustrating to man- age. As newer treatments become available (such as Bepreve and Lastacaft), the eye care specialist's toolbox grows, and more options may mean greater control in previously recalcitrant cases. Adopting a simple, tiered approach can simplify the process and ameliorate patients' symptoms in a step-wise manner.

Rajesh K. Rajpal, MD, is the medical director of Cornea Consultants, PC, McLean, Virginia, and a clinical associate professor at Georgetown University Medical Center, Washington, DC. He is a consultant to Allergan, Inc.; Inspire Pharmaceuticals; and Ista Pharmaceuticals, Inc. He is a speaker for Alcon Laboratories, Inc., and Bausch + Lomb. Dr. Rajpal may be reached at (703) 287-4122; rrajpal@seeclearly.com.

Dawn Williams is a fourth-year optometry student at the InterAmerican University of Puerto Rico. She acknowledged no financial interest in the products or companies mentioned herein.

Christine Burris Wisecarver, OD, is in practice at Cornea Consultants, PC, in McLean, Virginia. She acknowledged no financial interest in the prod- ucts or companies mentioned herein. Dr. Wisecarver may be reached at cwisecarver@seeclearly.com.