Articles: histamine.
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J. Allergy Clin. Immunol. · Feb 1997
ReviewAppraisal of the validity of histamine-induced wheal and flare to predict the clinical efficacy of antihistamines.
Antihistaminic drugs have been used successfully for many years in the treatment of allergic diseases. Second-generation antihistamines have fewer sedating side effects than first-generation agents, and the number of newer drugs available for clinical use is growing. Various methods have been used to assess antihistaminic activity, the most popular of which is the epicutaneous histamine-induced wheal and flare. ⋯ Studies with antihistamines have shown that certain drugs, such as cetirizine, are more suppressive than others (loratadine, terfenadine) in controlling the histamine-induced wheal and flare reaction in the skin. When the clinical efficacy of these medications is compared in clinical trials in seasonal allergic rhinitis and chronic idiopathic urticaria, all are equally efficacious in controlling symptoms. Although the histamine-induced wheal and flare reaction can serve as a useful clinical pharmacologic test to assess dose-response relations for an antihistamine, its lack of correlation with clinical responses among antihistamines indicates that this model should not be used to predict or compare clinical efficacies of antihistamines in seasonal allergic rhinitis and chronic idiopathic urticaria.
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Clinical Trial Controlled Clinical Trial
Effect of allergen challenge on airway responsiveness to histamine and sodium metabisulphite in mild asthma.
Airway responsiveness to histamine and methacholine, direct smooth muscle spasmogens, is increased following inhalation of allergen. Although the aetiology of this phenomenon is unclear, increased cellular or neural activity may be involved since allergen also induces increases in airway responsiveness to the mast cell stimulus adenosine-5'-monophosphate (AMP) and the neural stimulus bradykinin. ⋯ These data suggest that activation of airway sensory nerves is unlikely to contribute to the increase in airway responsiveness following inhalation of allergen. The previously observed allergen induced increase in airway responsiveness to bradykinin and AMP may involve non-neural pathways.
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Allergie et immunologie · Oct 1996
[Importance of plasma (histamine and tryptase) and urinary (methylhistamine) in peri-anesthetic anaphylactic and/or anaphylactoid reactions].
Histamine and tryptase, released during anaphylactoid reactions in anaesthesia, can be measured out by radioimmunoassay, provided that their own pharmacokinetic is respected. For two years, we have used sample kits in order to realize the measuring out of these mediators. The aim of this study was to evaluate the interest of these mediators within investigational procedures for anaphylactoid reactions. ⋯ Within minor clinical reactions (grade I), plasma histamine and urinary methylhistamine were the only mediators detected. In an anaphylactic reaction of grade II, which happened after the administering of vecuronium, tryptase was not detected. Therefore, these mediators give the anaesthetists the possibility to prove quickly the severity of the reactions and to direct the investigations very early towards the right way.
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Dermatology (Basel) · Jan 1996
Comparative StudyTachyphylaxis to histamine-induced wheal suppression by topical 0.05% clobetasol propionate in normal versus croton oil-induced dermatitic skin.
Patients often tell about reduced effectiveness of topical steroids on repeated use. Tachyphylaxis to these agents has been demonstrated in humans for vasoconstriction and histamine-induced wheal suppression in normal skin, but not in diseased skin. Relevance of these data to diseased skin is not clear. Further, the clinical impression does not appear to match tachyphylaxis shown in normal skin with regard to the time course. ⋯ Time courses of tachyphylaxis to the action of 0.05% clobetasol propionate were significantly different in normal skin and dermatitic skin. Complete tolerance occurred earlier in dermatitic skin compared to normal skin.
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Pruritus is a common symptom in uraemic patients and its aetiology is poorly understood, although several factors have been implicated, including high histamine plasma levels. The aim of the study was to evaluate plasma levels of histamine in patients on maintenance haemodialysis in relation to the presence of itching (35 pruritic patients = group A; 50 non-pruritic patients = group B). ⋯ However, no relationship was found between plasma histamine values and itching because groups A and B showed overlapping values and there was no correlation between the intensity of pruritus and plasma histamine concentrations in group A patients. In conclusion, we suggest that there is no evidence for plasma histamine playing a significant part in uraemic pruritus.