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)

Dermatitis caused by contact with tentacles of jellyfish was studied on 25 volunteers. Two tentacles cut from a living jellyfish, Carybdea rastonii, were applied on each of the forearms and skin reactions were observed. All volunteers complained of severe pain, which lasted from 10 min to 8 hrs. Erythema and wheal appeared within 3 to 4 min and enlarged for 15 to 20 min. Erythema subsided within 24 hrs to 3 days in all but two individuals. Seven to 13 days after the application, linear erythema and papulo-vesicular lesions with pruritus were observed on the forearms of 15 out of 25 volunteers tested. These flare-up lesions lasted for one week leaving slight pigmentation. Histological findings from the flare-up lesions corresponded to those of allergic contact dermatitis. The lymphocyte response to the jellyfish venom in the subjects who had recurring lesions was greater than that in either the subjects with no recurring lesions or the control group, who was never exposed to jellyfish.
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PMID:Cutaneous reactions caused by experimental exposure to jellyfish, Carybdea rastonii. 197 Mar 47

Neutrophil attractant/activation protein-1 (NAP-1) is a recently described cytokine that attracts neutrophils, but not monocytes or eosinophils. This leukocyte specificity is not absolute, in that NAP-1 attracts basophils and small numbers of lymphocytes. Our purpose was to determine in vivo effects of NAP-1, and to compare them to the reported action of the complement attractant, C5a. Intradermal injection into normal human subjects of 40 microliters of NAP-1, over a concentration range of 4 x 10(-8) M to 10(-6) M, caused no symptoms or signs such as wheal-and-flare, itching, induration, or tenderness. However, biopsies of injection sites showed perivascular neutrophil infiltration as early as 30 min, which increased at 1 and 3 h. The mean number of neutrophils per mm2 of dermis for 15 biopsies taken 3 h after intradermal injection of 2 x 10(-7) M or 10(-6) M NAP-1 was 164 +/- 41; the response to saline or a NAP-1 inactive fragment was 5 or less. Intradermal NAP-1 did not cause basophil or lymphocyte infiltration. Consistent with the absence of a wheal-and-flare, acid toluidine blue-stained sections showed no evidence of mast cell degranulation, in contrast to previously reported results with C5a. Thus, the predominant response by human subjects to intradermal NAP-1 was neutrophil accumulation in proximity to dermal blood vessels.
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PMID:Neutrophil recruitment by intradermally injected neutrophil attractant/activation protein-1. 202 77

This comparative trial (histamine dry skin prick test versus control prick test) evaluates with subjective and objective clinical methods (i.e. itch scores, wheal area, and wheal and flare area) and with laser Doppler flowmetry (multiple sites measured between 5 and 15 min after prick test) the effect of increasing the duration of the skin prick (1, 3 and 10 s). As compared with control prick tests, all objective clinical parameters after histamine prick test were significantly different from the control prick tests. There was no interaction between agonist-duration of prick test and clinical parameters. When present, itch was reported only after histamine prick test. Skin blood perfusion values were evaluated with Laser Doppler flowmetry at prick test sites and at 1 cm distance from the prick test site. At control and histamine prick test sites, increased blood flow values were observed and a moderate interaction between agonist-duration of prick test and repeated measurement was noted (one tail P less than 0.05); there were indeed lower values 9 min after histamine prick tests whatever the duration of the prick test. At 1 cm distance from histamine prick test sites, all skin perfusion measurements (either 5-8 or 11-14 min) showed increased values over data recorded after control prick test (P less than 0.0001). On pooled data recorded at distance from histamine or control prick tests, there was a significant interaction between agonist-duration of prick test and laser Doppler flowmetry (P less than 0.0004).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Skin response to histamine dry skin prick test: influence of duration of the skin prick on clinical parameters and on skin blood flow monitoring. 228 98

Histamine iontophoresis is demonstrated to be a reliable model for the study of inflammatory skin responses. It has the advantage of a non-invasive and uniform mode of application and is free of unwanted side effects. The wheal and flare responses to histamine are linearly related to dose over a wide range of stimulus strengths (r = 0.88). In summer, wheal responses were smaller, probably due to increased thickness of the epidermis. Female subjects generally expressed larger wheal responses than males, presumably due to differences in epidermal thickness and structure. There were significant regional differences in wheal, flare, and laser Doppler recorded flux responses. Ratings of itch sensations also showed clear, but less pronounced, differences of body regions. Significant regional differences of wheal and flare responses existed. Sensory discrimination of different stimulus levels was demonstrated with visual analogue scale ratings.
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PMID:Properties of transdermal histamine iontophoresis: differential effects of season, gender, and body region. 230 54

Recent case reports have suggested that H2-antihistamines used alone may be effective in the treatment of acute urticaria, a common complaint of patients presenting to the emergency department. This contradicts accepted doctrine on the treatment of acute urticaria. Based on theories of H1- and H2-receptor interaction at the cellular level, it has been stated that H2-blockade before H1-blockade may exacerbate symptoms. The purpose of our study was to compare diphenhydramine, an H1-blocker, with cimetidine, an H2-blocker, in a randomized, prospective, double-blind clinical trial. Ninety-three patients presenting to the ED with clinical evidence of acute urticaria were treated with either 50 mg diphenhydramine IM or 300 mg cimetidine IM. Patients' signs and symptoms were quantitated on a numeric scale before receiving medications and 30 minutes after treatment. Parameters measured included degree of itching, intensity and extent of wheals, degree of sedation, and perception of overall improvement. Each medication provided significant relief of itching and wheal intensity (P less than .0001). Sedation was caused by both diphenhydramine (P less than .0001) and cimetidine (P less than .0006). However, the degree of sedation caused by diphenhydramine was significantly greater than that caused by cimetidine (P = .0001). The perception of overall improvement was greater with cimetidine, with 87% of patients reporting improvement, whereas 76% of diphenhydramine-treated patients reported improvement. Our results indicate that cimetidine is efficacious as the initial treatment of acute urticaria and has less tendency toward sedation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of cimetidine and diphenhydramine in the treatment of acute urticaria. 240 34

Endothelin-1 (ET-1) induced hyperalgesia in rats, abdominal constrictions in mice, incapacitation in dogs, and, when injected intradermally into humans, caused wheal and flare responses, which were accompanied by itching. The ET-1 induced constrictions in mice were prevented by indomethacin. In contrast, indomethacin had no effect on the hyperalgesic responses in the rat. These results indicate that ET-1 may play a role in modulating pain.
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PMID:Endothelin-1 participation in overt and inflammatory pain. 247 19

Apart from increased production of immunoglobulin E antibodies and disturbed T-cell regulation, altered patterns of releasability of vasoactive mediators have been described in patients with atopic eczema. The best studied substance is histamine which is a classical inducer of pruritus in man. Elevated concentrations of histamine have been found in vivo in the skin and in the plasma of patients with atopic eczema especially during exacerbation of the disease. Similar findings have been described for other atopic diseases as extrinsic bronchial asthma. Histamine acts via characteristic receptors; symptoms as itch, wheal formation, mucus production, contraction of smooth muscle, tachycardia H2-effects include acid secretion in the stomach as well as the development of flush and itch reactions, blood pressure changes and cardiac arrhythmia. Of special interest is an inhibitory effect of histamine on lymphocyte reactions mediated via a H2-receptor. The existence of a new H3-receptor in the brain serving as autocrine feed-back inhibitor of histaminergic neurones has been established in the rat but not yet in man. In vitro an increased histamine releasability of peripheral leukocytes has been found after stimulation with a variety of different substances. The difference between patients with atopic eczema and normals is generally most pronounced after stimulation with anti-IgE. There is, however, a tendency towards an increased spontaneous histamine release compared to normals. The release reaction of histamine seems to occur more rapidly in atopics compared to normals.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Histamine and atopic eczema. 247 78

The objective of this double-blind study, which is part of a multicenter study, was to determine whether terfenadine (120 mg once daily) has similar efficacy and tolerability to the standard dosage of 60 mg twice daily in the treatment of chronic urticaria. Forty-one patients were randomly allocated to two parallel groups and treated for 2 weeks with either regimen. Evaluation of efficacy was based on rating scales for investigator and patient. Primary endpoints were itch, number of wheals, wheal size, and the overall rating of efficacy. A similar improvement was seen in all variables. There were no statistically significant differences between groups. Both treatments were well tolerated.
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PMID:Comparison of efficacy and tolerability of terfenadine administered once daily versus twice daily in patients with chronic idiopathic urticaria. 257 89

Hydroxyzine, a potent H1-receptor antagonist often used for relief of pruritus in patients with hepatic dysfunction, was studied in eight patients, mean age 53.4 +/- SD 11.2 years, with primary biliary cirrhosis. The patients ingested a single dose of hydroxyzine, 0.7 mg/kg (mean dose 43.9 +/- 6.6 mg). Before the dose, then hourly for 6 hours, every 2 hours from 6-12 hours, at 24 hours, and every 24 hours for 6 days, serum hydroxyzine and cetirizine were measured and an intradermal injection of 0.01 mL of a 0.1 mg/mL solution of histamine phosphate was performed. Wheals and flares were traced at 10 minutes and the areas were calculated. Mean peak hydroxyzine levels of 116.5 +/- 60.6 ng/mL occurred at 2.3 +/- 0.7 hours and mean peak cetirizine levels of 500.4 +/- 302.0 ng/mL occurred at 4.8 +/- 2.8 hours. The mean serum elimination half-life of hydroxyzine was 36.6 +/- 13.1 hours, and the mean serum elimination half-life of cetirizine was 25.0 +/- 8.2 hours. The mean hydroxyzine clearance rate was 8.65 +/- 7.46 mL/min/kg, and the mean volume of distribution was 22.7 +/- 13.3 L/kg. The mean wheal area was suppressed (P less than 0.01) from 1 to 120 hours, with maximal suppression from 2 to 48 hours. The mean flare area was suppressed from 1 to 144 hours, with maximal suppression from 3 to 24 hours (P less than 0.01). All patients became sleepy from 0.5 to 6 hours. Blurred vision, dizziness and dry mouth each occurred in two patients. Hydroxyzine elimination is impaired in patients with primary biliary cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The pharmacokinetics and pharmacodynamics of hydroxyzine in patients with primary biliary cirrhosis. 257 11

The objective of these three double-blind multi-centre studies was to determine whether terfenadine 120 mg once daily has similar efficacy and tolerability as the standard dosage of 60 mg twice daily in the treatment of chronic urticaria. A total of 252 patients were randomly allocated to two parallel groups and treated for 2 weeks with either regimen. Evaluation of efficacy was based on rating scales for investigator and patient, i.e. itch, number of wheals, wheal size and an overall rating of efficacy. A similar improvement was seen in all variables, and there were no statistically significant differences between treatment groups. The power of the studies combined is greater than 80%, i.e. sufficient to state convincingly that treatment effects are not different. Both treatments were also equally well tolerated.
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PMID:Terfenadine once daily in chronic urticaria. A multi-centre double-blind comparison of terfenadine once daily versus twice daily. 257 86


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