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

This article reviews the effect of H1 antihistamines on the pruritus of urticaria, from articles in which their therapeutic effect on chronic idiopathic and physical urticaria is assessed. In limited studies available pruritus improved concomitantly with wealing by an average of two thirds, though the response in individual patients was variable. In some physical urticarias the pruritus and wealing showed disproportionate improvement compared to erythema. The minimally sedating H1 antihistamines were as effective or more effective than classical H1 antihistamines. The dose of antihistamines that totally abolished a histamine weal only partly reduced urticarial weals (therefore by inference also of the associated pruritus). Additional therapy aimed at pruritogenic mediators other than histamine would be expected to improve urticarial pruritus.
 ...
PMID:H1 antagonists in the management of the itch of urticarias. 134 87

Substance P is a neuropeptide (contained in/and released from the A delta and C nerve fibers of the skin), which provokes erythema, edema, and pruritus after intradermal injection. Local pretreatment with capsaicin produces decreased substance P-dependent erythema, with edema similar to that observed before pretreatment with capsaicin. We injected histamine and in a parallel experiment, substance P in five volunteers before and after local treatment with capsaicin, with 48/80, after 5 days of hydroxyzine. The injection of SP provoked erythema centered by a wheal. After treatment with 48/80, SP provoked increased erythema and a wheal. After hydroxyzine treatment, the injection of histamine produced no erythema or edema in four of the five subjects, while SP provoked erythema in all five subjects and edema similar to that observed before treatment with hydroxyzine. These data support the hypothesis that substance P provokes erythema and edema both with histamine-dependent and histamine-independent pathways.
 ...
PMID:Substance P provokes cutaneous erythema and edema through a histamine-independent pathway. 137 8

The efficacy of cetirizine dihydrochloride, a new H1-antagonist claimed to have minimal sedative property was evaluated in 28 patients with chronic idiopathic urticaria. Cetirizine 10 mg and placebo were compared in a double-blind cross-over trial. Response was measured by patients with daily charts on itch and wheals. Response was also assessed by patients and investigators while on cetirizine and placebo on an analogue scale. The mean analogue score by the investigator while on cetirizine (64.6 mm) was better than while on placebo (47.0 mm) (p = 0.008). Reduction of itch with cetirizine was significantly greater than with placebo. The mean itch scores for placebo and cetirizine were 21.2 and 14.5 respectively (p = 0.01) showing a significant improvement of itch by cetirizine. The mean score for wheal response for placebo and cetirizine were 21.0 and 16.16 respectively (p = 0.07 NS) showing a reduction of wheal from cetirizine was greater than placebo but the difference was not statistically significant. The patients' mean visual analogue score for placebo was 38.4 and for cetirizine was 57.5 (p = 0.006). Cetirizine was significantly better in controlling symptoms of chronic urticaria than placebo. Five of the 28 (17.9%) patients reported mild drowsiness while taking cetirizine. Two patients reported drowsiness while on placebo. Tolerance was reported as good in 85%, moderate in 10% and bad in 5% according to patients' assessment, while tolerance was excellent and good in 80%, moderate in 15% of patients according to investigator's assessment.
 ...
PMID:Cetirizine vs placebo in chronic idiopathic urticaria--a double blind randomised cross-over study. 168 78

A double blind study against placebo was carried out in order to assess the inhibition induced by oxatomide gel in specific and aspecific cutaneous responses (prick test). Twenty allergic patients (8 M, 12 F) aged between 15 and 59 years (average 31) were treated for 7 days with oxatomide gel 5% or with placebo (2 applications a day). The results show a significant reduction of itching and of wheal size (considering either major diameter and area) only in the oxatomide group (p less than 0.01 between times and p less than 0.001 between treatments), whereas among controls itching remained unchanged and wheal size increased. During the follow-up a gradual return of wheal size to initial values in the patients treated was observed.
 ...
PMID:[Evaluation of the inhibition of allergen-specific and nonspecific skin responses by topical oxatomide]. 168 30

Skin reactions and itch or burning pain sensations following intradermal injection of the neuropeptide substance P and topical application of the substance P releasing agent mustard oil were studied in 20 atopic dermatitis patients and 20 healthy controls. Changes in skin blood flow were measured with a Laser Doppler flowmeter. Areas of wheal and flare reactions were evaluated planimetrically. Simultaneous with Laser Doppler flowmeter measurements, subjective itch and burning pain ratings were verbally reported on a category partitioning scale at 10-second intervals. Substance P evoked dose-dependent wheal, flare, and itch reactions in both patients and controls. However, substance P doses of 10(-9) -10(-11) mol elicited smaller flares in patients than in the controls whereas the wheal sizes were similar in both groups. Substance P-induced itch ratings were lower in patients at a dose of 10(-10) mol, and the onset of itching was delayed at all substance P levels applied. Mustard oil elicited similar neurogenic inflammatory reactions in both groups, although pain sensations were significantly delayed in atopic dermatitis patients at two mustard oil concentrations, which is further indication of a desensitization of afferent nerve endings contributing to the neurogenic inflammatory reactions in the skin of these patients.
 ...
PMID:Reactions to intradermally injected substance P and topically applied mustard oil in atopic dermatitis patients. 171 19

Double-blind, placebo-controlled studies were performed to assess the effect of 0.1% dimetindene gel on the itch threshold to intracutaneous histamine and on the weal and flare reaction after intracutaneous injection of histamine in normal volunteer subjects. Treatment of the forearm skin in 20 volunteers resulted in an increase in itch threshold with dimetindene gel compared to placebo. Treatment of the forearm skin with dimetindene gel in 32 volunteers had no significant effect on weal thickness in subjects treated for 10, 30 or 60 min, but there was a significant reduction in weal thickness in those subjects treated for 120 min. Topical dimetindene may be of value in treating conditions mediated through histamine release.
 ...
PMID:Efficacy of topical dimetindene in experimentally induced pruritus and weal and flare reactions. 187 44

Living lice and eggs were found in 19% of 2643 children examined in Israel. Boys and girls were equally infested. Bite reactions, pruritus, excoriations, lymphadenopathy, and conjunctivitis were the most common signs and symptoms. Bite reactions, pruritus, excoriations, and conjunctivitis were found more frequently in infested children than in noninfested children. Lymphadenopathy, eczema, influenza, herpes, crusts behind ears, blepharitis, seborrhea, psoriasis, erythema, vitiligo, secondary infections, and scars were equally common in both groups. The sequence of the skin reactions of a volunteer to continuous exposure to lice bites was as follow: phase I, no clinical symptoms; phase II, papules accompanied by pruritus of medium intensity; phase III, wheal formation immediately after the bite, followed by a delayed papular reaction and intense itching; phase IV, papular reaction with diminished reactivity of the skin and mild pruritus. Healed bite reactions reappeared when other parts of the skin were again exposed to the lice.
 ...
PMID:Clinical observations related to head lice infestation. 191 61

1. The aim of this investigation was to study the peripheral neural mechanisms of the C-fiber-mediated modalities of burning pain and itch by the use of microneurography of human unmyelinated afferents. 2. Sixteen stable recordings of single C-fibers and 6 multiunit recordings were obtained from the superficial radial nerves of volunteers. All units were excited by stimulating their receptive fields with von Frey bristles (range 10-600 mN), and all but four units were also driven by radiant heat stimulation. 3. Histamine was iontophoretically applied to the receptive fields of these units for 20 or 30 s and was found to provoke itching sensations lasting several minutes, together with wheal and flare responses. Subsequently a solution containing 20 or 30% mustard oil was applied to the receptive field of the respective unit, which provoked a sensation of burning pain. 4. One-half of the units were excited by histamine, and the median discharge rates derived from interspike intervals ranged from approximately 0.1 to 0.8 Hz. Mustard oil-induced activity was observed in all histamine-sensitive units and also in three single units and in one multiunit recording that revealed no histamine response. Median interval-derived discharge rates ranged from 0.2 to 1.2 Hz. 5. Analysis of the interspike interval distribution and of the autocorrelation function derived from the chemically induced discharges of single units provided no evidence for an encoding of itch and burning pain in different discharge patterns of units responding to histamine and to mustard oil.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Discharge patterns of human C-fibers induced by itching and burning stimuli. 191 73

Pruritus is a common symptom associated with chronic renal failure (CRF). But increased plasma histamine levels and skin mast cell proliferation previously reported in these patients did not correlate with the intensity of the pruritus. Since increased mast cell releasability was described in chronic idiopathic urticaria, we attempted to examine whether this mechanism could explain pruritus in patients with CRF. Twenty-five patients with end stage renal failure were skin tested with histamine, codeine, and compound 48/80. There were nine patients on continuous ambulatory peritoneal dialysis, eight patients on hemodialysis, (tested both before and after dialysis) and eight patients with advanced CRF. Wheal area after intradermal injection of three concentrations of the above substances was measured. In general, the wheal areas in all patients with CRF were either similar to or smaller than those of the control group who were without renal impairment. In conclusion, patients with CRF with or without dialysis therapy demonstrated unchanged or decreased skin test responses to histamine, codeine, and compound 48/80. Increased mast cell releasability cannot explain the pruritus in patients with CRF.
 ...
PMID:Cutaneous responses to histamine, compound 48/80, and codeine in patients with chronic renal failure. 195 8

A quantitative comparison was made of the effect of infiltration of local analgesics and topical analgesic cream (EMLA) on laser-induced pain and histamine-induced wheal, flare and itch. Wheal and flare were quantified by planimetry and analgesia was quantified by the pricking pain threshold to argon laser stimulation. The intensity of histamine-induced itch was scored on a 4-point scale. Local analgesics had no effect on the wheal area. The flare reaction was abolished by infiltrating lignocaine, and gradually inhibited by increased application times of EMLA. Itch was abolished after local lignocaine infiltration, but not significantly reduced after EMLA cream applied for less than 120 min, although the skin was anaesthetized to laser-induced pain. The reduction of flare area correlated to the level of analgesia, which may therefore reflect the cutaneous responsiveness to neurogenic inflammation. It is suggested that itch and pricking pain are mediated by different populations of nerve fibres, as itch can be evoked even when the sensation of pricking pain is abolished. Surgery, skin prick tests and other traumatic procedures should therefore be performed under local anaesthesia to reduce neurogenic inflammation.
 ...
PMID:A quantitative comparison of the effect of local analgesics on argon laser induced cutaneous pain and on histamine induced wheal, flare and itch. 196 96


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>