Nov. 16, 2010 -- A new preservative-free nasal spray may be a safe and soothing alternative for sensitive noses irritated by traditional nasal sprays.
A new study suggests that a preservative-free saline nasal spray that relies on an acidity to kill germs and remain sterile may offer a new way to treat sinus symptoms.
Researchers say pharmaceutical companies rely on chemical preservatives, such as benzalkonium chloride and phenylcarbinol, to destroy or slow the growth of potentially dangerous microorganisms that may enter the container after opening. But these preservatives can damage delicate tissues in the nose and cause unpleasant side effects such as burning or irritation.
"There is another way that you can preserve nasal sprays that is safe for consumer use," researcher Peter Hwang, MD, professor of otolaryngology at Stanford Medical Center, says in a news release.
Researchers say making the spray more acidic is an alternative way to maintain sterility of nasal and other solutions commonly used to deliver drugs to delicate areas.
"This also has potential for eye drops, medicated sprays, eardrops," Hwang says.
Making a Safer Solution
In the study, published in the Archives of Otolaryngology-Head & Neck Surgery, researchers evaluated the safety and tolerance of a preservative-free nasal spray that had been acidified by hydrochloric acid to a pH of 2.5 and then buffered by low concentrations of citric acid in 20 healthy adults.
The participants used the preservative-free solution in a saline nasal spray and a traditional saline nasal spray containing benzalkonium chloride twice a day for one week each, separated by a one-week washout period.
Before and after using each type of nasal spray, the participants filled out a questionnaire about their nasal symptoms and had a nasal endoscopic examination. Researchers also tested the contents of each nasal spray bottle for microorganism growth.
The results showed both nasal sprays remained sterile after one week of daily use and there were no differences in nasal symptoms or problems between the two groups.
But researchers stress that this was a small and short-term study, and more research is needed to ensure the safety and effectiveness of this new type of preservative-free solution.