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Nasal spray reduces infections with COVID
A study gives hope
Table of contents
Introduction
Well-known nasal spray shows protective effect against a corona infection
Azelastine is an active ingredient that has been used for decades against hay fever. Many over-the-counter nasal sprays contain azelastine. A new study from Saarland University now provides indications that azelastine nasal sprays can do more than just relieve allergies.
A spray with unexpected potential
While vaccinations remain the most important protective measure against a severe course of COVID-19, there are so far hardly any medications that can prevent infection with the corona viruses. Earlier laboratory studies had shown that azelastine also has antiviral properties – it can therefore directly inhibit viruses. The researchers from Homburg now wanted to investigate whether azelastine nasal sprays can contribute to the prevention of SARS-CoV-2 infections in healthy adults.
The study in a nutshell
- Period: March 2023 to July 2024
- Participants: 450 healthy adults
- Design: Double-blind, meaning neither the participants nor the researchers knew who received the real azelastine spray.
- Procedure: One half used azelastine nasal spray three times daily for 8 weeks, the other half a placebo.
- Control: Everyone was tested for SARS-CoV-2 twice per week.
Significantly fewer infections
The result was clear:
- In the azelastine group only 2.2% became infected, while in the placebo group it was 6.7%.
This corresponds to a risk reduction of about 70%. - Common cold viruses (rhinoviruses) also occurred significantly less often in the azelastine group.
- Side effects were rare and mild – mainly a bitter taste or slight nosebleeds.
How does azelastine work?
Azelastine not only blocks histamine (which triggers symptoms in allergies), but also seems to slow down several viruses, including SARS-CoV-2, influenza and rhinoviruses. It influences certain docking sites of the viruses in the nasal mucosa and thus makes it more difficult for them to enter the cells.
Why this is important
Even with a high vaccination rate, it is still possible to become infected with corona. A well-tolerated, over-the-counter nasal spray could help to further reduce the risk in everyday life.
However, the researchers emphasize that the results still need to be verified in larger studies.
Conclusion
An already established allergy spray could help to better protect against respiratory viral infections – including COVID-19. I recommend the use of azelastine nasal sprays to my patients when there is an increased risk of becoming infected with corona viruses. For example when another family member is ill, before large events such as concerts, before traveling by train or airplane, or if you frequently use public transport during the cold season.
Important note:
The content of this blog/newsletter is provided for general informational purposes only and does not replace personal medical advice, diagnosis, or treatment. The information presented here should therefore not be used as the sole basis for making health-related decisions. If you experience any medical complaints, you should in any case seek professional medical advice.
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I am Dr. Katja Aschenbrenner. When no one else can find the root cause, my work begins. I support people with persistent exhaustion, unclear symptoms, or chronic illnesses using an integrative and functional medicine approach.
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