Chloraseptic Allergen Block and Little Allergies Allergen Block, by Prestige Brands, are identical gels that claim to treat allergy problems. Just put this stuff under your nose and the allergens are drawn to it like flies on, well, you know. Is there any proof that it works? There must be because it is FDA approved. Not really. The FDA approved it as a device which really means nothing at all. The company claims it protects against ragweed, pollen, dust mites, pet dander and house dust but wouldn't a study or two be helpful? Not if you are in the business of making money. So, with a nice marketing plan and a good commercial, another so-called medical product is off to the races. Seems to me, though, that if having a gel under your nose is all you need to prevent allergies then why do my pediatric patients with boogers and snot underneath their noses still sneeze? Shouldn't that be a protective gel as well?