Unique Air-Liquid Interface Model Confirms Efficacy of Vicks First Defense

P&G Scientists have proven that a nasal spray can effectively guard against cold and flu viruses.

The groundbreaking study, reported in the journal Viruses, was the result of a collaboration between the P&G Singapore Innovation Center and the National University of Singapore. It involved developing an accurate representation of the human nasal lining by creating a state-of-the-art Air-Liquid Interface model using human nasal epithelial cells.

With this model, the researchers demonstrated that the Vicks First Defence Nasal Spray not only provides broad spectrum defence against respiratory viruses but is also well-tolerated for continuous use over a week.

The study was led by Professor De Yun Wang and Dr Hsiao Hui Ong from the National University of Singapore, alongside Dr Yong Chiat Wong from P&G Singapore Innovation Center. Dr. Wong stated “Our formula shows broad spectrum efficacy against both Rhinovirus and Influenza A and its variants, making it a strong ally during cold and flu season.”

Key to its effectiveness is hydroxypropyl methylcellulose (HPMC), a safe, well-tolerated ingredient, which serves as a physical barrier to protect nasal passages from infections. Additionally, they found that an acidic buffer can destabilize viruses outside epithelial cells, enhancing the protective benefits of the Vicks nasal spray compared to other market solutions.

At Procter & Gamble, we are dedicated to advancing health and wellness through science-based innovation in collaboration with leading academic institutions around the globe. As we advance our efforts with academic partners like the National University of Singapore, we invite you to explore how Vicks First Defence Nasal Spray can be an essential part of your health toolkit. For more details, read the full findings published in Viruses 2025, 17(3), 376 at Inhibitory Activity of Hydroxypropyl Methylcellulose on Rhinovirus and Influenza A Virus Infection of Human Nasal Epithelial Cells