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Histamine H2-receptor antagonists for urticaria
Zbys Fedorowicz1, Esther J van Zuuren, Nianfang Hu
1UKCC (Bahrain Branch), Ministry of Health, Bahrain, Box 25438, Awali, Bahrain. zbysfedo@batelco.com.bh
The Cochrane Database of Systematic Reviews
|March 16, 2012
Summary
H2-receptor antagonists showed limited effectiveness for urticaria treatment. Combination therapy with ranitidine and diphenhydramine improved urticaria resolution more than diphenhydramine alone, but evidence remains weak.
Area of Science:
- Dermatology
- Pharmacology
Background:
- Urticaria is a common skin condition causing itchy hives.
- Various subtypes and treatments exist, but H2-receptor antagonist efficacy is debated.
Purpose of the Study:
- To evaluate the safety and effectiveness of H2-receptor antagonists in treating urticaria.
Main Methods:
- Searched multiple databases (Cochrane, MEDLINE, EMBASE, LILACS) up to October 2011.
- Included randomized controlled trials on H2-receptor antagonists for urticaria.
- Excluded studies involving H1-antihistamines for chronic urticaria.
Main Results:
- Four small studies (144 participants) were analyzed.
- Ranitidine plus diphenhydramine improved urticaria resolution compared to diphenhydramine alone.
- Cimetidine did not significantly improve symptoms over diphenhydramine, but combinations showed benefit.
Conclusions:
- Limited, low-quality evidence from small, old studies with high bias risk.
- Current evidence does not support confident decision-making on H2-receptor antagonist use for urticaria.
- Reported symptom relief was minimal and unreliable.
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