People with eczema often take oral antihistamines hoping to ease relentless itching. But a new study finds they may do little to help—and could cause worrisome side effects.Researchers reviewed 47 clinical trials involving more than 6,200 children and adults with mainly moderate to severe eczema.The trials compared antihistamines, H2 blockers, and mast cell stabilizers to placebo—with and without standard treatments like moisturizers or steroid creams. The results: antihistamines produced only small, clinically unimportant improvements in eczema and itch severity and may not reduce sleep problems or flare-ups.The researchers say first-generation antihistamines probably increase drowsiness and sedation and may make patients more likely to stop treatment because of those side effects.Their conclusion: These “findings do not support their use in routine atopic dermatitis management.”Yet nearly half of eczema patients in the U.S. use oral antihistamines.The researchers say it's time for updated guidelines—ones that focus on what actually works, what's safe, and what patients really need.Source: The BMJ OpenAuthor Affiliations: McMaster University, University of Toronto, Harvard T.H. Chan School of Public Health, Children's Hospital of Philadelphia, University of Pennsylvania, Boston Children's Hospital, UMass Chan Medical School, University of Colorado School of Medicine.Sign up for our weekly HealthDay newsletter