Allergic conjunctivitis mast cell stabilizers

Mast cell stabilizers are an effective and safe treatment modality for allergic conjunctivitis. They are useful in patients who have perennial allergic conjunctivitis and as a prophylaxis fc>r seasonal allergic conjunctivitis. Mast cell stabilizers are effective only when used before the onset of allergic symptoms, because most drugs in this class have a typical therapeutic effect that occurs in 7 days to 14 days. Because there is a delay in noticeable clinical improvement with most mast cell stabilizers, concurrent therapy with other agents may be necessary for immediate relief. Nedocromil is an exception in this category, because it provides a more rapid relief of symptoms, usually within 15 to 30 minutes. 

The mast cell stabilizers currently for ophthalmic use are nedocromil and pemirolast. These drugp are used for the prevention of eye itching caused by allergic conjunctivitis. The mast cell stabilizers act by inhibiting the antigen-induced release of inflammatory mediators (eg, histamine) from human mast cells. 

If mast cell stabilizers or multiple-action agents are not successful, a trial of a topical NSAID is appropriate. Ketorolac is the only approved topical agent for ocular itching. NSAIDs do not mask ocular infections, affect wound healing, increase intraocular pressure, or contribute to cataract formation like the topical corticosteroids. However, for allergic conjunctivitis, topical ketorolac is not as effective as olopatadine or emedas-tine in trials.15 Full efficacy of ketorolac takes up to 2 weeks.17... 

Pemirolast (AlamasI) [Mast Cell Stabilizer] Uses Allergic conjunctivitis Action Mast cell stabilize Dose 1—2 gtt in each eye qid Caution [C, /-] Disp Opthal soln SE HA, rhinitis, cold/flu Sxs, local irritation EMS None OD Unlikely to cause life-threatening Sxs... 

In moderate to severe cases of allergic conjunctivitis, treatment considerations also include mast cell stabilizers, antihistamine-mast cell stabilizer combinations, oral antihistamines, NSAIDs, and, in severe cases, topical steroids. 

Mast cell stabilizers include cromolyn sodium 4% (Opticrom, Crolom) and lodoxamide tromethamine 0.1% (Alomide), which are currently approved by the U.S. Food and Drug Administration for VKC but offer off-label relief for allergic conjunctivitis. Other mast cell stabilizers include pemirolast (Alamast) and nedocromil sodium 2% (Alocril), with both approved for treatment of itching in allergic conjunctivitis. Perennial allergic conjunctivitis may be treated with mast cell stabilizers year round. 

Indications Bronchial asthma, pruritus of allergic conjunctivitis Category Mast cell stabilizer Half-life 3.3 hours... 

The mast cell stabilizers are used in combination widi other drugs in the treatment of asdima and odier allergic disorders, including allergic rhinitis (nasal solution), and in the prevention of exercise-induced bron-chospasm. When die mast cell stabilizers are used in conjunction widi odier antiasdima dni, a reduction in dosage of die dni may be possible after using die mast cell stabilizer for 3 or 4 weeks. These dni may be given by nebulization, aerosol spray, or as an oral concentrate... 

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