Allergic conjunctivitis is usually a bilateral condition caused by pollen or other allergens. In cases where only one eye comes into contact with the allergen, the response may be unilateral. Typical symptoms are red, itchy eyes associated with tearing and burning that gradually disappear when the patient is no longer in proximity to the inciting allergen. The condition is often associated with runny nose, itching of the soft palate of the mouth, and sneezing. Approximately 70% of patients with allergic conjunctivitis also have asthma and/or atopic dermatitis.
Cold compresses and tear substitutes are useful in relieving burning and dry eyes in patients with a mild allergy. However, many patients require more aggressive therapy with selective histamine-1 (H1)-receptor antihistamines (e.g., levocabastine) that relieve itching and watery eyes. Ketotifen (available OTC as Alaway, Zaditor, Zyrtec Itchy-Eye Drops, and Claritin Eye) is a multiple-action H1-receptor antihistamine that prevents the activation of inflammatory mediators. While first- and second-generation oral antihistamines are effective in treating allergic conjunctivitis, topical ophthalmic products are superior in treating this condition.
For rapid but short-lived relief of redness, patients may choose a topical decongestant such as naphazoline, tetrahydrozoline, or oxymetazoline. These are available as single-ingredient OTC preparations, including All Clear, Murine, and Visine, respectively. Preparations such as Naphcon-A, Opcon-A, and Visine-A are combinations of a topical decongestant and an antihistamine. When recommending topical decongestants, it is important to note that these products can cause further complications such as conjunctivitis medicamentosa and irritation if used over long periods of time.
If OTC medications do not provide effective relief within 7 days or the condition worsens, patients should be referred to their physician for further investigation. Prescription medications for allergic conjunctivitis include mast-cell stabilizing agents such as sodium cromolyn and nedocromil, as well as anti-inflammatory agents and topical nonsteroidal anti-inflammatory drugs (NSAIDs), namely ketorolac.
US Pharmacist © 2010 Jobson Publishing
Cite this: Managing Common Eye Conditions in the Pharmacy - Medscape - Apr 01, 2010.