Experimental Nasal sprays are being developed that appear to reduce nasal viral load considerably

From a preprint:

This one has not been tested in humans but looks great in the lab.  Might be used for prophylaxis when entering enclosed spaces.  It is an OTC sinus nasal spray whose active ingredients are xylitol and grapefruit seed extract.

Xylitol has a long history of being safe and beneficial in preventing bacterial pathogen
infections.14 It is considered a prebiotic due to its positive effect on the microbiome, reducing
pathogenic proliferation.15 The use of xylitol in oral health to prevent dental caries and
periodontal disease has been well documented as safe and effective…  Because there are no risk factors in using the X/GSE combination therapy, and the
nasal spray is over the counter available without prescription, and the spray allows for
comfortable long term mask wearing, adoption of this preventive anti-viral therapy should be

 Here‘sone other nasal spray, nitric oxide, that has been tested on humans, but the press release never says whether it improved their clinical course.  It did reduce viral load.  Since the product is applying for an EUA, it does not need to show clinical benefit, only that its net effect is presumed to be better than nothing. 

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1 year ago

Am I missing something here? Use the nasal spray to help prevent illness from Covid AND wear a mask?

Meryl Nass, M.D.
Meryl Nass, M.D.
1 year ago

I'm just the messenger. I doubt these will prevent Covid, but they may have a role for some people, and reduce viral load, perhaps slowing the infection down or leading to a milder case.

Has not been tested in people yet. Very preliminary.
We know the authors threw in the sentence about masking to cya.


1 year ago

I was thinking the mask comment was a CYA thing too. If nothing else, maybe those with chronic allergies will have another option for treating allergic rhinitis that doesn't include a steroid. 🙂

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