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Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Doxepin hydrochloride, a tricyclic antidepressant, was evaluated in a double-blind, placebo-controlled crossover trial for the treatment of chronic idiopathic urticaria in 16 adults. Efficacy was evaluated by symptom scores, concomitant antihistamine use, and suppression of histamine- and codeine-induced wheal response. Doxepin-treated subjects experienced fewer lesions (p less than 0.001), less waking hours with lesions (p less than 0.01), lesser degree of itch and/or discomfort (p less than 0.001), and less swelling or angioedema (p less than 0.001) as compared to placebo-treated subjects. Doxepin-treated subjects required less daily concomitant antihistamine use (mean 0.13 tablets versus 1.48 tablets, p less than 0.05). Doxepin also significantly suppressed histamine- and codeine-induced cutaneous wheal response as compared to placebo. Lethargy was commonly observed but diminished with continued use. Dry mouth and constipation were also commonly observed. We conclude that doxepin is an effective agent for the treatment of chronic idiopathic urticaria.
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PMID:Efficacy of doxepin in the treatment of chronic idiopathic urticaria. 378 54

Fifty patients with chronic idiopathic urticaria were studied to compare responses to treatment with doxepin (10 mg three times a day) and with diphenhydramine (25 mg three times a day). All patients had an evaluation that failed to disclose a cause for their disease. Therapeutic response was assessed according to the suppression of symptoms and symptom diary scores of daily itching and frequency, number, size, and duration of hives. Total clearing of the pruritus and urticarial lesions occurred in 43% of the patients while receiving doxepin and in only 5% while receiving diphenhydramine (p less than 0.001). Partial or total control of the pruritus and hives was noted in 74% of the patients receiving doxepin and in only 10% of those receiving diphenhydramine (p less than 0.001). Doxepin induced markedly less sedation (22%) than diphenhydramine (46%) (p less than 0.05). Dermatopathologic categories included (1) urticaria simplex, (2) lymphocytic urticaria, and (3) leukocytoclastic urticaria. Patients with urticaria simplex had a more favorable response to doxepin than the two other groups.
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PMID:Double-blind crossover study comparing doxepin with diphenhydramine for the treatment of chronic urticaria. 388 24

Randomized double-blind trials using doxepin and several conventional antihistamines were carried out for treatment of patients with idiopathic cold urticaria. In the first double-blind trial, eight of nine patients preferred doxepin (10 mg three times daily) to cinnarizine (10 mg three times daily). In the second double-blind trial, the results of ice cube tests suppressing the effect of cyproheptadine (4 mg three times daily), doxepin (10 mg three times daily), and hydroxyzine (10 mg three times daily) did not statistically differ. However, doxepin was subjectively the most effective and it had fewer side effects than other treatments that were compared. Doxepin effectively suppressed the wheal and itching responses and shortened the duration of the wheal response in the ice cube test in all patients with cold urticaria who were studied.
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PMID:Comparison of cinnarizine, cyproheptadine, doxepin, and hydroxyzine in treatment of idiopathic cold urticaria: usefulness of doxepin. 648 Sep 53

Frequent antihistaminic side effects noted during treatment of depression by tricyclic drugs, as well as the high affinity of tricyclic antidepressants for H1 receptors in mouse neuroblastoma cells, suggest possible useful antihistaminic properties. We investigated the antipruritic activity of topically applied 5% solutions of doxepin hydrochloride (Adapin; Sinequan) and amitriptyline hydrochloride (Elavil) and compared such activity to that of a 5% solution of diphenhydramine and vehicle alone. Test solutions were applied to 25-cm2 areas on the flexor forearms of forty subjects, and the development of itch to single drops of eight dilutions of histamine phosphate instilled in each area was reported over a 3-minute period. The lowest concentration of histamine able to elicit unequivocal itching in each treated area was the histamine itch threshold (HIT). Doxepin, amitriptyline, and diphenhydramine all produced significantly higher mean and median HITs (p less than 0.01 than did vehicle control. Sixty-eight percent of subjects had a HIT greater than or equal to 2 x 10(-4) mg/ml in doxepin-treated areas versus 58% for amitriptyline, 53% for diphenhydramine, and 25% for vehicle. Our data suggest that tricyclic antidepressants are effective topical antipruritic agents.
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PMID:Inhibition of histamine-induced pruritus by topical tricyclic antidepressants. 729 24

Previous studies show that oral antihistamines affect the weal and flare response to intradermal injections of the inflammatory mediators platelet-activating factor (PAF) and bradykinin (BK). The aim of this study was to compare the effects of terfenadine (an H1-antagonist) and cimetidine (an H2-antagonist) on weal and flare responses to PAF and BK in healthy non-atopic human volunteers. The effects of doxepin on PAF responses were investigated, as there is evidence that doxepin may have direct anti-PAF effects in addition to its known antihistaminic actions. Terfenadine significantly reduced weal and flare responses to PAF (mean reduction 53 and 73%, respectively) and flare responses to BK (mean reduction 78%) but had no effect on weal responses to BK. Doxepin significantly reduced both weal and flare responses to PAF (mean reduction 43 and 68%, respectively, at higher doses of PAF). Cimetidine had no effect on weal or flare responses to PAF or BK. These findings suggest that the flare response to intradermal BK is mediated via histamine release while the weal response is not. The effects of the various antagonists of PAF-induced responses suggest that its effects too may be mediated via histamine, the similarity of the effects of terfenadine and doxepin on these responses indicating that the effects of doxepin may be due to its known antihistamine activity rather than to any specific PAF-antagonistic properties. Platelet-activating factor (PAF) is a phospholipid which is released from a wide range of cell types and also from vascular endothelium. PAF is formed by the conversion of ether-linked phospholipids initially to the biologically inactive lyso-PAF and then by acetylation to PAF. Intradermal injection of PAF in human skin causes vasodilatation and increased vascular permeability, producing a weal and flare response with accompanying pruritus. Bradykinin (BK) is a vasoactive polypeptide formed by the action of enzymes known as kallikreins on inactive precursors called kininogens. Its effects include an increase in blood flow and vascular permeability and stimulation of the release of prostaglandins and histamine. On intradermal injection in human skin it causes a weal and flare response with associated pain rather than pruritus. Previous studies have suggested that the weal and flare response to PAF may be mediated in part by histamine release. Given that BK is known to cause histamine release it appears possible that the responses to both compounds may be modified by conventional antihistamines. Experiments based on this premise have found that antihistamines have a pronounced effect on the flare response to PAF but a less marked effect on weal responses. The weal response to BK was unaffected by systemic antihistamines but studies have produced conflicting results with regard to effects on the flare response. The aim of this study was to compare the effects of terfenadine (an H1-antagonist) and cimetidine (an H2-antagonist) on PAF- and BK-induced weal and flare responses in healthy, non-atopic human volunteers. Based on the treatment of cold urticaria it has been suggested that doxepin, which has known H1- and H2-antagonistic effects, may in addition show specific anti-PAF activity. We compared the effects of doxepin on PAF-induced intradermal responses with those of terfenadine and cimetidine in this study.
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PMID:Effects of H1- and H2-antihistamines on platelet-activating factor and bradykinin-induced inflammatory responses in human skin. 868 66

The primary treatment of urticaria involves identification and discontinuation of the offending agent. Addition of an antihistaminic agent may then be necessary to control pruritus. Because of variable response rates between patients, several alternative agents may need to be tried before the most effective regimen is found. Based on the studies reviewed here, it appears that low-dose doxepin (10 mg po tid) is a potentially effective and well-tolerated alternative in patients who do not respond to conventional antihistamines. This success may be in part due to the more potent H1- and H2-blocking properties associated with doxepin. Data regarding the topical use of doxepin are less convincing; however, the drug appears to have some clinical use for the short-term treatment of pruritus. Doxepin cream does not appear to be as effective as systemic therapy, and adverse effects (including sedation) and drug interactions are still problematic. Topical use may be best suited to conditions involving intact skin that do not require application to large areas of the body, thereby reducing systemic absorption and adverse effects.
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PMID:Doxepin in the management of pruritus associated with allergic cutaneous reactions. 916 61

The search for evidence based information and its evaluation for planning the care of a woman with pruritus without visible signs on her skin is exemplified and described in this article. Literature was sought with the key words "itch", "pruritus", and "elderly" in medline, Cinahl and the Cochrane library. Retrieved studies were appraised by the criteria for valid information of evidence based nursing. Most pruritus studies were about pruritus with skin rash or about pruritus connected to liver or renal failure. Randomised controlled trials about the treatment of pruritus were characterised by small sample sizes or were done with only men or women. The little knowledge found in these studies did not help resolve the complex individual situation of the patient. Treatment suggestions from the studies: to assess the causes and exacerbating factors of pruritus; to wash the skin with water only, e.g. without soap; to emulsify the skin with Vaseline or oil at least once daily; to prevent too much heat by covering the patient just enough for him or her to feel no cold; prescribing Atarax, a histamin inhibitor of the first generation at night time; to try the antidepressant drug Doxepin; and emulsification with alcohol, menthol and cool water. There is no evidence to predict results of any one of these suggested interventions. Further research regarding the pathophysiology and the effectiveness of interventions against pruritus is needed.
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PMID:[Pruritus without skin manifestation--what kind of state of the art nursing intervention?]. 1461 17