Nasal Spray for FluI use Xlear nasal spray (http://www.vitacost.com/XlearNasalWashwithXylitol), to which I have added a half-dropperful of colloidal silver (Vitacost and many other sites sell CS), and spray each nostril once in the AM and PM when I have a sinus infection, and also whenever I am going to be in a public area where I could be exposed to flu or other viruses or bacteria.