Common allergy medications known as antihistamines do not provide meaningful relief for people with eczema, according to research from McMaster University released on July 30. The study found that these widely used medications fail to significantly improve symptoms such as dry, itchy, red, and irritated skin associated with atopic dermatitis.
The research team conducted a systematic review of 47 randomized trials involving 6,230 children and adults with mild to severe eczema. This analysis, described as the most comprehensive to date on the topic and published in the BMJ on July 29, examined both modern second-generation antihistamines—sold under brand names like Reactine, Claritin, Aerius, Allegra, Rupall, and Blexten—and older first-generation antihistamines such as Benadryl, Chlor-Tripolon, and Polaramine.
Results showed that second-generation antihistamines produced only small changes in eczema severity and itch that did not meet thresholds considered important by patients or clinicians. First-generation antihistamines were found to produce no noticeable improvement in symptoms but likely increased the risk of cognitive impairment—including drowsiness, confusion, slowed thinking or impaired performance at school or work—which may persist for days after use. Among newer second-generation drugs studied (bilastine, desloratadine and fexofenadine), cognitive effects were much lower.
"The findings support moving away from routine antihistamine use in atopic dermatitis care and toward treatments that are more effective, less likely to cause harm, and are more certain to control eczema inflammation. This may also help keep eczema control as simple and straightforward as possible, with patients focusing on high-value treatments," said Chu of McMaster University's Department of Health Research Methods.
Researchers emphasized that oral antihistamines remain appropriate for treating other allergic conditions such as hay fever or hives. The study was commissioned by the American Academy of Allergy Asthma & Immunology along with the American College of Allergy Asthma & Immunology through their Joint Task Force on Practice Parameters for living atopic dermatitis guidelines. The review used the GRADE system developed at McMaster University for rating evidence certainty.
