Why a common allergy nasal spray might prevent COVID

A common over-the-counter nasal spray grabbed headlines and social media buzz recently as a simple, surprising way to reduce your chances of getting COVID-19.  Experts say the research behind the headlines is promising but early. The key may be that azelatine spray, used to treat seasonal allergies, helps keep the nose lining calm.

As WebMD reported, the study was published in JAMA Internal Medicine and showed that healthy adults younger than 65 who used the spray three times daily for eight weeks had a 67% reduced risk of testing positive for COVID, compared to people who used a placebo spray. They also had a reduced risk of being diagnosed with the common cold. This latest study builds on nearly a dozen others pointing to azelastine's multi-factor potential to prevent COVID. 

Azelastine is FDA-approved for rhinitis, inflamed nasal passages that usually come with a runny or stuffy nose. Anyone with rhinitis who takes azelastine might be "less susceptible to super infections, like COVID or other viruses, because it does have multiple mechanistic effects," said allergist Jonathan A. Bernstein, MD, an expert on azelastine and an adjunct professor at the University of Cincinnati College of Medicine. (He was not involved in the study.)

Research suggests that azelastine may calm a type of protein in the nose that sometimes triggers nasal hyperreactivity, said Bernstein, who has studied the protein, called TRPV1. When the protein is overactive, it can trigger inflammation and damage the nasal lining, making it easier for viruses to slip through. By preventing the protein from becoming overactive, azelastine helps keep the lining intact and less inflamed, making it harder for viruses to penetrate and infect underlying cells, Bernstein said. 

For those interested in trying the spray, talk to a doctor first — and don't rely on the spray alone to protect you against COVID, especially if you are 65 or older, have a weakened immune system or have a medical condition that puts you at a higher risk of a severe infection. Experts said the spray should not take the place of good hygiene practices and COVID-19 vaccines.

Read why scientists are focused on the nose when it comes to COVID prevention.

Featured image at top: Illustration of Covid-19 protein/Provided.