Can an Over-the-Counter Nasal Spray Prevent COVID and Colds?

"Every winter, I prepare for my clinic schedule to fill up with patients experiencing runny noses, coughs, and fevers caused by viruses, such as rhinoviruses, influenza, and COVID-19. I also prepare that I'll get sick myself at least once, no matter how cautious I am. While vaccines, handwashing, and high-quality face masks are beneficial, I have always wondered why we cannot yet block respiratory viruses at the place where they enter the body: the nose."

"From there, they attach to and invade the cells in our nose, leading to inflammation. That inflammation produces symptoms, such as congestion, runny nose, sore throat, and, in some of us, fever, chills, and body aches. In theory, if you can reduce the ability of a virus to attach and replicate in the nose, you could stop infection altogether. This is the scientific rationale for studying nasal sprays, lozenges, or other topical agents."

Respiratory viruses typically enter the body through the nose, attach to nasal cells, and trigger inflammation that causes congestion, runny nose, sore throat, and systemic symptoms in some people. Topical nasal agents aim to block viral attachment and replication at that entry point. Azelastine, an antihistamine used for allergic rhinitis, shows laboratory activity against multiple steps of viral infection. A randomized trial in Germany enrolled about 450 healthy adults and reported fewer COVID-19 and common cold infections with azelastine nasal spray. The trial was small, industry-funded, and involved younger, healthier participants, so larger multicenter studies are needed to confirm effectiveness before widespread use.

Read at Psychology Today