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Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Exposure of the eye to airborne particles in patients predisposed to allergy often results in the signs and symptoms of allergic conjunctivitis such as red, itchy eyes and ocular discharge. The mediators of these allergic symptoms include histamine, inflammatory substances such as prostaglandins, and other products of arachidonic acid metabolism (ie, leukotrienes). Ketorolac tromethamine is a nonsteroidal anti-inflammatory agent that inhibits the activity of cyclooxygenase, one of the two major enzymes responsible for the conversion of arachidonic acid to inflammatory substances. A multicenter patient survey was performed to evaluate the effectiveness of topical ketorolac tromethamine in treating the symptoms of allergic conjunctivitis. After ocular administration of ketorolac tromethamine, 90% (246/272) of patients reported that their eyes felt better. Eighty-four percent (173/206) of respondents rated ketorolac tromethamine as good to excellent in relieving their overall symptoms of ocular allergy, and 86% (217/251) of patients found the study drug produced good to excellent relief of their ocular itching usually within minutes to 1 hour of administration. Results of this survey found ketorolac tromethamine is effective in relieving ocular itching, the hallmark symptom of allergic conjunctivitis. In addition, these results provide further evidence that the products of arachidonic acid metabolism contribute to the symptoms of allergic conjunctivitis.
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PMID:Results of a survey of patients with ocular allergy treated with topical ketorolac tromethamine. 859 40

Topically administered ketorolac (Acular), a cyclooxygenase inhibitor, has recently been reported as clinically beneficial for treating allergic conjunctivitis. The ability of ketorolac to relieve the itching associated with allergic conjunctivitis is intriguing because cyclooxygenase inhibitors are not regarded as useful in treating allergic dermatoses and prostaglandins (PG) do not elicit an itch response in human skin. To gain further insight into the mechanisms involved in the antipruritic activity of ketorolac, we used a method of reproducibly assessing ocular surface itch responses in the guinea pig. The measurement of conjunctival pruritus involved a recently developed behavioral model whereby hind limb scratching episodes directed toward the afflicted area were quantified. Itch-scratch episodes have previously been delineated from foreign body and pain sensations, which do not evoke such a behavioral response. Ketorolac significantly inhibited the itching associated with experimental allergic conjunctivitis. The basis of this antipruritic activity may be ascribed to preventing the biosynthesis of itch-producing PGs because ketorolac inhibited arachidonic acid-induced pruritus. In contrast to skin studies, PGE2 and PGI2 were found to be potent pruritogens at the guinea pig ocular surface. PGD2 was a weak pruritogen, and PGF2 alpha and the thromboxane-mimetic U-46619 produced no meaningful response. Further studies involving selective agonists and antagonists suggested that EP1 receptors, IP receptors and PGD2-sensitive receptors may mediate prostanoid-induced conjunctival itching. No evidence for the involvement of other prostanoid receptor subtypes was obtained. Although the EP1 receptor antagonist AH 6809 and the DP receptor antagonist BW A868C inhibited PGE2- and PGD2-induced itching, respectively, neither antagonist alone significantly affected the itching associated with experimental allergic conjunctivitis. A combination of AH 6809 and BW A868C, however, did exhibit antipruritic activity. It appears that for effective relief of itching in allergic conjunctivitis, it is not sufficient to block the effects of a single pruritogenic PG. It is preferable to reduce the participation of all pruritogenic PGs by either using combined receptor antagonists or by using a cyclooxygenase inhibitor such as ketorolac to block their biosynthesis.
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PMID:Characterization of receptor subtypes involved in prostanoid-induced conjunctival pruritus and their role in mediating allergic conjunctival itching. 885 86

Seasonal allergic conjunctivitis is rarely associated with permanent vision impairment; however, it is a relatively common condition that may compromise the quality of life. It may, in extreme cases, impair daily activities, including work. Numerous treatment options have become available for the relief of acute symptoms. Avoidance should always be the first line in therapy but, in most cases, is not practical, especially with pollen allergies. The use of saline eyedrops is simple and nontoxic, and it is effective in up to 30% to 35% of cases. It can and should be added to all other remedies to reduce adverse effects and cost by decreasing the need for other therapeutic options. Antihistamines and decongestants are useful treatment choices for the majority of cases. Ketorolac tromethamine may be helpful in relieving pruritus, but it offers little advantage over topical antihistamines. Corticosteroids may be used for severe cases for a limited time. If topical corticosteroids are being considered, an ophthalmologist should be consulted. Cromolyn sodium and lodoxamide ophthalmic solution may be helpful in the prophylaxis of symptoms during the allergy season, but these agents require frequent dosing. Olopatadine hydrochloride is a mast cell stabilizer and antihistamine that can be dosed twice a day. Immunotherapy is effective and should be offered to those who are intolerant or have allergic conjunctivitis refractory to medications.
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PMID:Seasonal allergic conjunctivitis: overview and treatment update. 1047 15

This multicenter, double-masked, randomized, parallel-group study compared the efficacy and safety of ketorolac tromethamine 0.5% ophthalmic solution with levocabastine 0.05% and ketorolac tromethamine vehicle in patients with seasonal allergic conjunctivitis. One drop of ketorolac, levocabastine, or vehicle was instilled in each eye four times daily for 6 weeks. In the majority of efficacy variables, ketorolac produced the greatest improvements, followed by levocabastine and vehicle. Ketorolac was significantly more effective (P < .05) than vehicle in reducing mean itching scores, palpebral hyperemia, bulbar hyperemia, and edema. Patients treated with ketorolac reported significant improvements (P < .05) in their ability to sleep and to concentrate on work, compared with those who received vehicle. No significant differences were noted among the treatment groups in safety or tolerability. Ketorolac tromethamine 0.5% ophthalmic solution instilled four times daily is effective and safe in reducing the signs and symptoms of seasonal allergic conjunctivitis.
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PMID:Efficacy and safety of ketorolac tromethamine 0.5% and levocabastine 0.05%: a multicenter comparison in patients with seasonal allergic conjunctivitis. 1101 60