treatment plan

A New Tool for Managing Allergic Response

BY BRUCE E. ONOFREY, RPH, OD

With so many antihistamines, mast cell inhibitors and non-steroidal anti-inflammatory agents available today, you may wonder if any of them are actually safe and effective in treating seasonal allergy, anterior uveitis, giant papillary conjunctivitis (GPC) and postoperative inflammation following cataract surgery.

A new addition to this category of drugs that I like to call "immune-modulators" is loteprednol etabonate, a site-specific topical corticosteroid designed to be deactivated by a single reaction after performing its therapeutic role. This rapid deactivation allows the compound to exert the beneficial effects without exerting the most common adverse effects of steroids.

Loteprednol is available from Bausch & Lomb Pharmaceuticals as a 0.2 percent suspension, marketed as Alrex, and a 0.5 percent suspension, marketed as Lotemax. You can treat ocular allergy and contact lens related conjunctivitis with Alrex; Lotemax is recommended for uveitis and postop management of inflammation. Alrex is similar in structure to prednisolone, but it is missing the number 20 ketone group, which has been shown to increase the risk of steroid cataract. Dosage is based upon the severity of inflammation, but the suggested dosing frequency for allergic disease is four times a day.

Safety and Efficacy Review

Long-term treatment of hay fever conjunctivitis, GPC and other conditions with corticosteroids is generally considered inappropriate due to possible adverse effects, such as steroid glaucoma and cataracts, which create an unacceptable risk-benefit ratio. In a six-week study with Alrex, there was no difference in intraocular pressure between the treated group and the placebo group.

Individuals who develop significantly elevated intraocular pressure during treatment with corticosteroids are classified as "steroid responders." In a study of 19 known steroid responders, Lotemax was compared to prednisolone 1%, four times a day for 42 days. The average intraocular pressure in the Lotemax group was 20mm Hg compared to 26.6mm Hg for the prednisolone group.

Alrex was administered to allergic conjunctivitis patients for up to three weeks prior to the height of the pollen count. Reduction in both clinical signs and symptoms was statistically significant in the treated group.

Mast cell inhibitors are valuable for managing mild to moderate GPC, but not for moderately severe to severe GPC, in which case patients should discontinue contact lens wear until their inflammation subsides.

In one study, loteprednol effectively treated the signs and symptoms of 113 GPC pa-
tients. An additional 37 patients were allowed to continue contact lens wear during treatment. Neither group reported any significant adverse effects of therapy.

In another study of 175 patients with acute anterior uveitis, patients were treated with either Lotemax or 1% prednisolone acetate. The reduction in anterior chamber cell and flare, pain and photophobia was statistically the same between the two treatment groups.

Loteprednol was compared to a placebo in a group of 424 postop cataract patients. Clinical signs of erythema, corneal edema and ciliary flush and clinical symptoms of photophobia, pain and tearing were all significantly reduced in the loteprednol group as opposed to the placebo group.

The efficacy and safety of loteprednol is quite impressive, yet it does not replace the antihistamines, mast cell inhibitors and other immune-modulators. Rather, it enhances the category, giving primary care clinicians an additional valuable tool to use in our fight against disorders of the immune system.

Dr. Onofrey, editor and author of various ophthalmic texts, practices in Albuquerque.