NasalGuard ® Airborne Particle Blocker® NasalGuard is an electrostatic topical nasal gel that prevents airborne particles from entering the nose. The product is drug-free and safe for pregnant or nursing women, children, and those concerned about potential drug interactions with other medications. NasalGuard protects against virtually all types of contaminants in any location. Users can count on it to work in their homes, offices, and other environments where airborne particles may present a health hazard. The product works immediately upon application and lasts up to six hours. NasalGuard gel uses a cationic (positively-charged) polymer that creates a safe the electrostatic field around the nasal passages that traps oppositely charged particles and repels similarly charged particles to reduce inhalation of most harmful airborne particles before they enter your body.