Can carbon dioxide help with nasal allergies?
Sep 7, 2011, 11:26 a.m.
"I must say, it's not a very attractive treatment," Nelson said.
He also pointed to what he saw as a weakness in the study: the placebo. Instead of comparing CO2 against some other gas, the researchers only gave placebo patients a nosepiece to insert.
That makes it unclear, Nelson said, if CO2 has some distinct effect, or if it was simply the intranasal pressure that somehow brought some people relief.
But Casale said that in an earlier study -- this one of people with seasonal allergies -- the researchers did use air in the placebo group, and the CO2-treated patients had greater symptom improvement.
Casale also pointed out that an advantage CO2 may have over antihistamines (both nasal spray and pill) and corticosteroids is that it works quickly. So the therapy might best fit into the nasal-allergy armament as an occasional, "as-needed" fix.
But that's still under study, Casale said. It also remains unclear why intranasal CO2 would be helpful against allergy symptoms, if that turns out to be the case.
Besides nasal steroids and antihistamines, some other nasal allergy treatments include nasal washes, which remove allergens from the nostrils, and allergy shots -- which may be recommended for specific allergies that do not improve with medication.
SOURCE: http://bit.ly/pugLiv Annals of Allergy, Asthma & Immunology, online August 19, 2011.