Loading ...

TOPLINE:

The use of second-generation H1-antihistamines was not associated with an increased risk for dementia in aging patients with chronic urticaria (CU), chronic sinusitis (CS), or allergic rhinitis (AR). However, in patients with AR, their use was linked to a modestly increased risk for dementia compared with the use of intranasal corticosteroids, possibly reflecting a protective effect of intranasal corticosteroids rather than harm from antihistamines.

METHODOLOGY:

• Researchers emulated a target trial using real-world data from electronic health records to assess a possible association between the use of second-generation antihistamines and the risk for dementia in patients with type 2 chronic inflammatory disease, including CU, CS, and AR.
• Patients aged 50 years or older with two subsequent records of the same allergic condition and no history of dementia were included; treatment groups were users of first-generation H1-antihistamines, second-generation H1-antihistamines, or non-antihistamine alternatives (intranasal steroids for AR and CS and oral steroids for CU).
• After propensity score matching, 4825 antihistamine users with CU, 21,611 with CS, and 36,802 with AR were paired with equal-sized non-antihistamine comparator groups; the mean ages ranged from 59.7 to 61.1 years, and women comprised about 71.3%, 55.9%, and 61.2% of the respective cohorts.
• The occurrence of dementia was assessed over a maximum of 5 years from treatment prescription.

TAKEAWAY:

• Across all three conditions, the use of any antihistamine was not associated with a higher risk for dementia than the use of non-antihistamine comparators.
• The risk for dementia did not differ significantly between users of second- and first-generation antihistamines; in patients with CU or CS, the risk was similar between users of second-generation antihistamines and non-antihistamine comparators.
• The use of second-generation antihistamines was associated with a modest but statistically significant higher risk for dementia in patients with AR than the use of intranasal corticosteroids (hazard ratio, 1.239; P for log-rank = .007).

IN PRACTICE:

“Overall, our findings support the continued use of sgAH [second-generation antihistamines] in type 2 inflammatory diseases without concerns regarding dementia risk,” the authors of the study wrote. “Lower dementia rates in patients with AR treated with corticosteroids might be associated with the protective effects of corticosteroids rather than harmful effects of sgAH.”

SOURCE:

Pavel Kolkhir, MD, Charité-Universitätsmedizin Berlin, Berlin, Germany, was the corresponding author of the study, which was published online on June 05, 2026, in The Journal of Allergy and Clinical Immunology: In Practice.

LIMITATIONS:

The analysis was limited by its retrospective design and the absence of a dose-response assessment. Because antihistamines can be obtained over the counter, assignment to treatment strategies may have been inaccurate. In addition, potential long-term effects could have been overlooked.

DISCLOSURES:

The authors reported receiving no source of funding. Several authors reported serving as speakers, consultants, or advisors and receiving research funds, lecture honoraria, or institutional support from multiple sources.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.