Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a multicenter, double-masked, clinical study, we compared the ocular safety and efficacy of ketorolac 0.5% ophthalmic solution with placebo in alleviating the signs and symptoms of allergic conjunctivitis. The study was conducted in 93 patients who received one drop of the appropriate treatments in each eye, four times a day, for seven days. Of these subjects, 74 were evaluated for efficacy. The principal clinical sign of allergic conjunctivitis, conjunctival inflammation, and six allergic symptoms (itching, swollen eyes, burning or stinging, discharge or tearing, foreign body sensation, and photophobia) were evaluated by the investigators at midweek (day 3 or 4) and at the end of the study (day 7 or 8). Ketorolac was superior to placebo in reducing conjunctival inflammation (p = 0.003) and itching (p = 0.020), the principal clinical symptom, at the final examination. In addition, ketorolac was favored over placebo in reducing the other five symptoms evaluated. On the day of final examination, overall therapeutic response evaluated by the investigators rated ketorolac as superior to placebo (p = 0.007). A significant placebo effect was noted in this study, as has been previously reported in clinical studies of allergic conjunctivitis patients. Results of this study demonstrate that 0.5% ketorolac ophthalmic solution used topically four times daily, for seven days, was effective in alleviating the principal sign and the symptoms associated with allergic conjunctivitis.
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PMID:Double-masked, paired-comparison clinical study of ketorolac tromethamine 0.5% ophthalmic solution compared with placebo eyedrops in the treatment of seasonal allergic conjunctivitis. 823 4

The therapeutic utility of cyclooxygenase (CO) inhibitors, such as ketorolac, in reducing the inflammatory events associated with allergic conjunctivitis is not unexpected since prostanoids (PG) elicit conjunctival redness (PGD2, PGE2, PGF2 alpha), edema (PGD2, TxA2), eosinophil infiltration (PGD2, PGJ2) and mucous cell discharge (PGD2, PGJ2, TxA2). Recently, topically administered ketorolac has also been reported to alleviate the itching associated with allergic conjunctivitis. This was viewed as intriguing since CO inhibitors are not regarded as useful for treating itching dermatoses and PGs do not elicit itching when applied to the skin. In order to investigate the antipruritic activity of ketorolac, we developed a model for reproducibly measuring ocular surface itch responses. The model involves itch-scratch responses to pruritogens applied locally to the ocular surface. Painful and foreign body stimuli do not produce an itch-scratch response. Unlike reported skin studies, PGE2 was a potent itch-producing substances in the conjunctiva. PGD2 was weakly pruritogenic but PGF2 alpha and the TxA2-mimetic U-46619 were inactive. The PG precursor arachidonic acid was also a potent pruritogen and its effects were inhibited by ketorolac pretreatment. Ketorolac also dose-dependently inhibited the itching associated with experimental allergic conjunctivitis. It appears that PGs are potent itch-producing substances in the conjunctiva and the anti-itch efficacy of ketorolac in allergic conjunctivitis appears to involve inhibition of conjunctival PG biosynthesis from arachidonic acid.
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PMID:The pruritogenic and inflammatory effects of prostanoids in the conjunctiva. 859 Feb 66

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

The efficacy of topical ketorolac 0.5% in treatment of vernal keratoconjunctivitis (VKC) was evaluated in a randomised double-blind prospective trial in 21 patients. Ketorolac treated eyes showed 50.7% reduction in main symptoms of itching compared to 33.3% relief in placebo treated eyes after 2 weeks of treatment (p < 0.01). Photophobia, ropy discharge, and conjunctival injection also lessened by 39.9%, 31.6%, and 39.1%, respectively, in ketorolac treated eyes compared to 23.8%, 17.3%, and 20.3% in placebo group. Transient stinging sensation was observed in 3 (14.3%) patients on ketorolac therapy. This study shows efficacy of ketorolac 0.5% solution in controlling symptoms in VKC.
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PMID:Topical ketorolac 0.5% solution for the treatment of vernal keratoconjunctivitis. 947 21

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

Seasonal allergic conjunctivitis is rarely associated with permanent vision impairment; however, it is a relatively common condition that may compromise the quality of life of patients with this diagnosis. In extreme cases daily activities, including work, may be compromised. Numerous treatment options have become available for the relief of acute symptoms. Corticosteroids may be used for severe cases for a limited time. If topical corticosteroids are being considered, an ophthalmologist should be consulted. Decongestants and antihistamines are useful treatment options for the majority of cases. Antihistamines, either topical or oral, should be the first-line therapy. Ketorolac may be helpful in relieving pruritus but offers little advantage over topical antihistamines. Sodium cromoglycate and lodoxamide may be helpful in the prophylaxis of symptoms during the allergy season but require frequent dosing. Immunotherapy is effective and should be offered to those who are intolerant or refractory to medications. Obviously, avoidance should always be the first choice in therapy but in most cases is not practical, especially with pollen allergies. The use of saline eyedrops is simple, nontoxic and is effective in up to 30-35% 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.
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PMID:Seasonal allergic conjunctivitis. 1509 55