Nasal sprays and COVID: An over-the-counter nasal spray long used to treat seasonal allergies may also help prevent COVID-19 infections, according to results from a clinical trial in Germany.
The spray contains the antihistamine azelastine, which earlier studies have shown can act as an antiviral against several respiratory infections, including influenza, RSV, and Covid-19.
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Researchers at Saarland University Hospital tested the spray in 450 healthy adults, average age of 30. Half of the group used azelastine three times a day, while the others used a placebo. Participants took regular Covid tests over nearly two months. At the end of the trial, only 2.2% of those using azelastine became infected, compared with 6.7% in the placebo group. The spray also appeared to reduce other respiratory infections.
Scientists are not entirely sure how azelastine works but suggest it may bind to the virus in the nasal lining and block its ability to replicate or interfere with the ACE2 receptor that Covid uses to enter cells.
“Our findings suggest azelastine could serve as a scalable, over-the-counter prophylactic against Covid, especially in high-risk settings like crowded events or travel,” said Dr. Robert Bals, professor of internal medicine and pneumology at Saarland and the study’s senior author.
The study, published in JAMA Internal Medicine, had limitations: participants were young and generally healthy. Experts warn that larger trials are necessary, especially for older adults and those with compromised immune systems.
