- The over-the-counter nasal spray azelastine may reduce your risk of COVID-19, according to one study.
- Azelastine may also shorten how long you’re sick and reduce your risk of other viruses like the common cold.
- Doctors explain how it works, plus whether you should try it during COVID season.
While staying up to date with your vaccines, regular hand-washing, and avoiding crowds or wearing a mask in crowded settings can all help protect you from viruses like COVID-19, scientists continue to look for other strategies and treatments that can help keep you healthy. One study, for instance, found a surprising link between the nasal spray azelastine and COVID risk. Read on to discover what the researchers found, plus how to apply their findings to your healthy routine.
According to a phase 2 clinical trial published in JAMA, using azelastine (an antihistamine nasal spray used to treat allergy symptoms and sold under the brand name Astepro Allergy) may help fend off COVID-19 and the common cold. For the randomized, double-blind, placebo-controlled study, researchers recruited 450 healthy volunteers in Germany. Of those, more than 99% had received the COVID-19 vaccine at least once.
The participants were split into two groups: One used an azelastine nasal spray in each nostril at least three times a day for about 56 days. The other used a placebo spray. Everyone was tested for COVID-19 twice a week.
Meet the experts:Jamie Alan, Pharm.D., Ph.D., an associate professor of pharmacology and toxicology at Michigan State University; Amesh A. Adalja, M.D., an assistant professor at the Johns Hopkins Bloomberg School of Public Health; Thomas Russo, M.D., a professor and chief of infectious diseases at the University at Buffalo in New York; William Schaffner, M.D., is an infectious disease specialist and professor at the Vanderbilt University School of Medicine
The researchers discovered that people in the azelastine group were about three times less likely to contract COVID-19 compared to those in the placebo group. Ultimately, just five people in the azelastine group (or 2.2%) tested positive for the virus, while 15 (6.7%) tested positive in the placebo group. People in the azelastine group also had a positive test for less time than their placebo-using counterparts (3.4 days compared to 5.14 days).
It doesn’t stop there: People in the azelastine group were also less likely to get any type of virus, including the common cold. The researchers discovered that only 8.4% of people in the azelastine group contracted a virus compared to 18.8% in the placebo group. The azelastine users reported only being sick for 1.73 days compared to 2.75 days in the placebo group.
Those are some pretty impressive findings, and it’s not the only data to suggest that azelastine may help lower your risk of getting sick. While doctors say azelastine may be a promising option to lower your risk of COVID, they want you to keep a few things in mind before running to your local pharmacy to stock up.
How does azelastine help prevent COVID and the common cold?
This study simply found a connection between using azelastine and a lowered risk of getting COVID-19 and other viruses—it didn’t determine an exact reason for this. But doctors say there could be a few things behind this.
For allergies, azelastine works by blocking histamine, a substance in the body that causes allergy symptoms, explained Jamie Alan, Pharm.D., Ph.D., an associate professor of pharmacology and toxicology at Michigan State University. “This is an antihistamine similar to Claritin or Zyrtec,” she said. “Azelastine is found typically in nasal sprays and eye drops.”
Azelastine also interferes with the function of proteins in viruses, making them less likely to be able to infect you, said Amesh A. Adalja, M.D., an assistant professor at the Johns Hopkins Bloomberg School of Public Health.
It seems to be able to inhibit the H2 receptor—a type of histamine receptor—which may impact how well a virus is able to get into your cells, explained Thomas Russo, M.D., a professor and chief of infectious diseases at the University at Buffalo in New York. “It appears to block viral attachments and maybe even moderate the immune response,” he said.
Inflammation may be a factor, too, Alan said. “I hypothesize that by using a nasal antihistamine, it would reduce the local response in the upper respiratory system, and therefore would reduce the local inflammation,” she said. “By reducing the local inflammation, it would be theoretically harder for a virus to attach and infect the upper respiratory system.”
Azelastine was first explored as a potential treatment for COVID-19 earlier on in the pandemic. There is some research to suggest azelastine may bind to a receptor that SARS-CoV-2 uses to access your cells, and it also may reduce viral load in your nasal passages. There’s other datato suggest that azelastine may also work against other viruses, including RSV and the flu.
Potential side effects of azelastine
While azelastine is considered a safe medication and is designed for long-term use, it comes with a risk of potential side effects. According to the National Library of Medicine, those may include:
- Bitter taste
- Nasal burning, pain, or discomfort
- Sneezing, runny nose
- Headache
- Sore throat
- Dry mouth
- Nosebleeds
- Dizziness
- Nausea
- Tiredness
Participants in both groups had side effects, but they were more common in the azelastine group. Those included bitter taste, nosebleeds (not many, but in 6.6% of the azelastine group compared to 4% of the placebo group), and fatigue.
Should you use azelastine to help lower your risk of COVID?
Doctors agree that azelastine may be helpful in lowering your risk of COVID—but more research is needed. “This is a phase 2 clinical trial, so the intervention will need more study before it can be confirmed as an effective prophylactic,” Dr. Adalja said.
But azelastine “does seem to have some antiviral properties,” said William Schaffner, M.D., an infectious disease specialist and professor at the Vanderbilt University School of Medicine. “Who knows? You might reduce your risk of RSV and influenza as well,” he said. “There seems to be no risk to using the medications.”
Alan agreed, noting that there’s likely no harm to using azelastine as long as you’re not allergic to any of the ingredients in the nasal spray.
But Dr. Russo pointed out that it’s tricky to use a nasal spray several times a day. “The data suggest that if you use this three to five times a day, it may be similar to decreasing the likelihood of contracting COVID as getting the vaccine,” he said. “But it’s really hard to take a medication once a day, let alone five times a day.” For many people, it’s ultimately easier—and cheaper—to just get the vaccine, he said.
Dr. Schaffner agreed. “Getting people to be compliant with this over the entire COVID season is substantial,” he said.
That said, Dr. Russo noted that there may be some benefit in using azelastine before a big event. “You may think, ‘I’m going to a wedding and it’s going to be a high-risk situation.’ So, you might start taking this a few days beforehand and a few days afterward as extra protection,” he said.
As there’s no data comparing azelastine to more traditional methods of preventing COVID-19, like getting the vaccine and wearing masks, doctors recommend doing those first. “This should not be a substitute for vaccination,” Dr. Schaffner said.
Dr. Adalja agreed. “In the best-case scenario, it will likely have a complementary role to vaccines—especially if shown to block infection, which vaccines against COVID are not able to do durably—and possibly provide protection against viruses for which there are no vaccines,” he said. But ultimately, doctors say that more research is needed first.
Read the full article here