Does nitric oxide nasal spray (Enovid/VirX/FabiSpray) help prevent or treat COVID-19?


The Enovid/VirX/FabiSpray nitric oxide nasal spray (NONS) looks promising, but we need more data to fully understand both safety and effectiveness. One thing is clear – this spray won’t make you bulletproof. It should be seen as a layer of protection, not a replacement for other precautions or treatments. This spray is available in several countries, but not yet in Canada or the United States, due to different regulatory requirements.

*This post was updated on Aug 21, 2023 to clarify that we don’t yet know impact on symptoms or disease severity

Read more below about what we do and don’t know about this nitric oxide nasal spray.

What is it?

Enovid, also sold as VirX or FabiSpray, is a nasal spray that may help prevent or treat COVID-19. This product has a proprietary formulation that creates nitric oxide when the spray is released from the bottle. Nitric oxide can kill viruses, regulate your immune response, and dilate (open) your blood vessels. Importantly, the amount of nitric oxide in this product is tightly and predictably dosed. Nitric oxide is not something you want to mess with!

Is it safe and effective?

This nitric oxide nasal spray (NONS) has been tested in several small human clinical trials, with encouraging results, but there is a lot we don’t yet know. Here are some highlights:

➡️ Safety: Overall, this nasal spray product looks very safe. There have been no serious adverse health events recorded in clinical trials spanning over a thousand patients across Canada, UK, India, and Thailand. Notably, these trials have not included pregnant women, children, or people with medical conditions. The most common side effect is nasal irritation.

➡️ Prevention: There is modest evidence that NONS can reduce the risk of developing COVID-19, likely by blocking viral replication and helping your body clear the virus before it takes hold. A study among university students in Thailand found a roughly 4 fold lower infection rate among students who were exposed to COVID-19 if they opted to use NONS following exposure (6% versus 26%). A large, randomized, placebo-controlled Phase 3 trial is underway to validate this preliminary result.

➡️ Treatment: We don’t yet know how NONS affects symptoms or disease severity, because relevant studies have not yet been done. However, there is strong evidence that treatment with NONS following infection can help clear the virus more quickly *from the nose*. Two different trials found similar results – roughly 95% lower viral load within 24 hours and 99% less virus by 72 hours, Similarly, a study in India reported that NONS shortened the time from infection to PCR negative status by 3 days. It remains to be seen how helping clear the virus more quickly from the nose translates into the whole body.

Where can I get it?

NONS is approved and available in select pharmacies in Israel, and Indonesia (under the brand name Enovid) and in Thailand, Singapore, Hong Kong, South Africa, Malaysia, Cambodia, and Germany (under the brand name VirX). It is also available in India, with prescription, under the name FabiSpray.

Canada and the United States have not yet approved this product, due to different regulatory requirements. The FDA recently told the makers (SaNOtize) that they will not approve it for treatment unless they can prove a reduction in hospitalizations and deaths – reduction in viral load doesn’t cut it for this agency. In Canada, it’s unclear what the hurdle is, but it’s likely a similar story regarding inadequate data to meet their standards. We may see approval for prevention next year after a large Phase 3 trial is completed. Read more about regulatory hurdles in the last link below.

The Bottom Line:

Enovid / VirX/ FabiSpray is a nitric oxide nasal spray that could be a promising addition to our COVID-fighting toolkit. Yet, it’s by no means a silver bullet, or a reason to forgo well-established precautions and treatments. Expect to use this nasal spray several times a day during high-risk exposures or during infection. These products are not yet approved in Canada or the US, but things may change next year when Phase 3 data become available.

Note: Nitric oxide nasal sprays are NOT the same as COVID-19 vaccines with nasal delivery. Check out the link below for more information on nasal delivery vaccines, which are being developed in the US, and already approved in other countries.