Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A large variety of topical substances can provoke wheals of human skin within 30 minutes. The usual term for this phenomenon, "contact urticaria," is too constricting and can lead to faulty diagnosis. Sometimes, the clinical expression is limited to erythema; less often, its sole manifestation is pruritus. The author proposes that contact urticaria is a spectrum ranging from urticaria through erythema to pruritus alone. This spectrum was demonstrated experimentally with three familiar urticariogens: cinnamic aldehyde and sorbic and benzoic acids. The nature of the immediate reaction depended on the concentration: wheals were induced with the highest tested concentration, erythema with a five-fold dilution, and pruritus alone with a 25-fold dilution.
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PMID:The spectrum of contact urticaria. Wheals, erythema, and pruritus. 230 63

To investigate the mechanisms of non-immunologic contact urticaria (NICU), the effect of 120 mg of terfenadine (H1-antagonist) on contact reactions to methyl nicotinate, diethyl fumarate, benzoic acid, cinnamic acid, cinnamic aldehyde and dimethyl sulfoxide was studied in 20 subjects. Erythema and edema were observed visually, and the changes in the skin blood flow were monitored with laser-Doppler flowmetry. Terfenadine did not have any significant inhibitory effect on erythema or edema from 6 contact urticariants tested, but it inhibited erythema and edema of prick test reactions to histamine. Non-specific histamine release from mast cells does not seem to be the mechanism of NICU from these substances.
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PMID:Terfenadine does not inhibit non-immunologic contact urticaria. 288 50

In the present study we examined the effects of chlorpheniramine and ranitidine, indomethacin, BW755C (an inhibitor of cyclo-oxygenase and lipo-oxygenase enzymes of arachidonic acid metabolism), dexamethasone, and capsaicin on nonimmunologic contact urticaria (NICU) induced in the guinea pig ear by benzoic, acid cinnamic acid, cinnamic aldehyde, methyl nicotinate, diethyl fumarate, or dimethyl sulfoxide. The intensity of edema in the urticarial reaction was quantified by measuring the ear thickness. Antihistamines inhibited reactions to intradermal histamine but not to agents causing NICU. Indomethacin and dexamethasone inhibited reactions to cinnamic acid and cinnamic aldehyde but not to other NICU agents. BW755C and capsaicin had no effect on reactions to any of the NICU agents. Mast cell degranulation during the reaction was not seen in histologic sections. Histamine and capsaicin-sensitive nerves did not seem to be essential for the development of NICU in the guinea pig ear. The details of the inhibitory effects of indomethacin and dexamethasone are not clear, but it seems probable that more than one mechanism is involved in NICU due to different agents.
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PMID:Pharmacological studies on nonimmunologic contact urticaria in guinea pigs. 310 19

To investigate the mechanisms of non-immunologic contact urticaria (NICU), the effects of 1g + 1g of acetylsalicylic acid (ASA) on contact reactions to methyl nicotinate, diethyl fumarate, benzoic acid, cinnamic acid, cinnamic aldehyde and dimethyl sulfoxide were studied in 21 test subjects. Erythema and edema reactions were observed visually, and the changes in the skin blood flow were monitored using laser-Doppler flowmetry. ASA had a significant inhibitory effect on erythema from all 6 agents and also on edema from all substances except dimethyl sulfoxide. The mechanism of the effect may be a result of the inhibitory influence of ASA on prostaglandin bioformation. Thus, to avoid false negative test results, non-steroidal anti-inflammatory drugs should not be used during NICU tests.
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PMID:Acetylsalicylic acid inhibits non-immunologic contact urticaria. 355 89

In order to find the most suitable animal species for studies on nonimmunologic contact urticaria (NICU), human NICU agents: 20% benzoic acid (BA), 10% sorbic acid (SA), 15% cinnamic acid (CA), 20% cinnamic aldehyde (CAL), 1.0% diethyl fumarate (DEF), 0.2% methyl nicotinate (MN), all in absolute ethyl alcohol, and 100% dimethyl sulfoxide (DMSO) were each applied to the earlobes of guinea pigs, rats, and mice. Guinea pig ear reacted with swelling to all agents tested. The mean maximal increase in thickness of the guinea pig ear, measured with a micrometer, was 114 +/- 46%. No response to BA, SA, CA, DEF, or MN was noted in the rat or mouse ear. However, DMSO and CAL caused significant ear swelling both in the mouse and the rat. Thus, the guinea pig ear is more sensitive to a variety of human NICU agents than is rat or mouse ear. The striking differences in species reactivity to NICU agents suggest the possibility that there are several mechanisms (mediators) involved in reactions to different substances. The guinea pig ear swelling test remains the best quantitative animal method available for screening human NICU agents.
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PMID:Species specificity of nonimmunologic contact urticaria: guinea pig, rat, and mouse. 404 Sep 28

The decrease in the swelling capacity and the length of the refractory period after nonimmunologic contact urticaria produced by one application of six human nonimmunologic contact urticaria agents was studied with the use of the guinea pig ear test. On retesting 1 day later, all substances (benzoic acid, cinnamic acid, cinnamic aldehyde, diethyl fumarate, methyl nicotinate, and dimethyl sulfoxide) showed reactions decreased by at least 50%. This decrease was most marked with cinnamic aldehyde (91% decrease), cinnamic acid (88%), and benzoic acid (86%). The tachyphylaxis was not specific to the substance producing it; reactivity to other contact urticaria agents decreased as well. The refractory period was 4 days after methyl nicotinate, 8 days after diethyl fumarate and cinnamic aldehyde, and 16 days after the other agents. These results suggest the following practical application: there is a need for (1) appropriate scheduling in the reuse of animals for testing for nonimmunologic contact urticaria and (2) an awareness of possible false-negative results in human tests for this form of urticaria because of tachyphylaxis.
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PMID:Long refractory period after one application of nonimmunologic contact urticaria agents to the guinea pig ear. 407 49

Inhibition (quenching) of contact sensitization by cinnamic aldehyde (CA) reportedly occurs from eugenol (E) and d-limonene (d-L). Experimentally the former inhibited nonimmunologic contact urticaria (NICU) from CA in seven of eleven test subjects, which prompted a search for possible mechanisms, including chemical interaction, altered absorption, and anti-inflammatory activity, and competitive inhibition. Mixtures of CA and E and CA and d-L showed no chemical changes or intermolecular bonding. Absorption was not increased by cellophane tape stripping, and neither E nor d-L inhibited urticaria formation following stimulation of skin of five subjects with dermographism. Competitive inhibition at the receptor level may best explain the quenching phenomenon observed. Additional factors are presented that complicate the already numerous caveats in interpreting test results in NICU.
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PMID:The effect of quenching agents on contact urticaria caused by cinnamic aldehyde. 669 99

The authors followed the frequency of fragrance contact sensitization in Hungary in a multicentre study in the years 1998 and 1999. A total of 3,604 patients were tested with fragrance mix (FM), and positive reactions were observed in 294 (8.2%). In 160 FM hypersensitive patients, the study was continued with patch testing of the mix constituents (cinnamic alcohol, cinnamic aldehyde, eugenol, amyl cinnamic aldehyde, hydroxycitronellal, geraniol, isoeugenol, oak moss absolute). Of the patients tested, 70.6% produced positive reactions to the constituents. FM contact sensitization was mainly observed in female patients (74.4%). The incidence of contact urticaria in FM hypersensitive patients was 6.1%. Simultaneous patch test trials of other environmental contact allergens, in both early and late evaluations, mainly confirmed hypersensitivity reactions to balsams. Female dominance of hypersensitivity reactions observed during testing the individual components of the mix was striking (82.4%). In positive skin reactions, cinnamic alcohol, isoeugenol and oak moss provoked skin symptoms most frequently. We also tested the 104 patients who produced negative reactions to FM with the constituent individual allergens, with 11.9% positive incidence. The clinical symptoms of the patients were above all manifest in the form of contact eczema, located on the hands, face, eyelids and axillae. With this study, the authors, members of the Hungarian Contact Dermatitis Research Group, call attention to one of the most frequent allergens in the environment.
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PMID:Multicentre study of fragrance allergy in Hungary. Immediate and late type reactions. 1219 Jun 20