May 24, 2021
5 min read

Coronavirus and sildenafil: a possible treatment?

There’s been some research into whether sildenafil (brand name Viagra) may improve some of the more serious symptoms of COVID-19. There’s promising data, but not enough to start prescribing it regularly to people with COVID-19. If you have coronavirus, and you’ve been prescribed sildenafil, you can continue taking it as directed.

Disclaimer

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.


The coronavirus pandemic upended our daily lives, leaving many of us looking for ways to take back some control. But while sildenafil (brand name Viagra) might be a miracle treatment when it comes to getting an erection, it hasn’t yet been proven to be an effective treatment for COVID-19. 

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Does sildenafil treat coronavirus?

Sildenafil is not a cure for coronavirus and is not currently considered a treatment for COVID-19. 

There’s ongoing research to see if sildenafil can help COVID patients breathe better and reduce the need for hospitalization or ventilators (Lomakin, 2020). Other researchers have outlined why they think this prescription drug might help with COVID-19, but the evidence is limited (Mario, 2020).

How does sildenafil help you get an erection?

There’s a natural substance in the body called nitric oxide, which promotes the production of a chemical called cGMP. cGMP causes the blood vessels in your penis to open up, allowing blood to flow in and produce an erection. Anything that disrupts that blood flow can make it difficult to get or keep an erection.

Sildenafil works by preventing the breakdown of cGMP in your body, so once it’s been produced by nitric oxide, it stays active and maintains strong blood flow into the penis (Ghalayini, 2004).

But if you thought sildenafil was only used to treat erectile dysfunction, you’d be wrong. The drug has also been approved to treat a lung condition called pulmonary arterial hypertension. Pulmonary arterial hypertension is a rare condition characterized by high blood pressure in the blood vessels that supply the lungs. Sildenafil has been shown to lower the pressure there, alleviating both symptoms and disease progression. 

Sildenafil and the lungs

Sildenafil works in the lungs the way it works in the penis—by opening up the blood vessels and making them larger, allowing the blood to flow there more easily. Think of your blood vessels like a highway. Sildenafil converts your two-lane highways to eight-lane highways, essentially reducing the traffic congestion and allowing the blood to flow more easily.

So how does that work when it comes to COVID-19? That seems to be a little different. 

There’s been a lot of research into other disease processes that sildenafil can disrupt. Most prominently, researchers showed that the drug reduces immune system activity there in rat models, which is essential when it comes to coronavirus (Kosutova, 2018). That’s because most lung damage in people with severe COVID-19 is caused by our immune system trying to kill the virus rather than by the virus itself (Chen, 2020). 

In addition, there is evidence that nitric oxide, the component that causes the blood vessels to dilate in the first place, might actually contribute to a better prognosis in patients with severe COVID-19. And while sildenafil doesn’t seem to increase nitric oxide levels directly, it has the same effect as the molecule in some regard (Dal Moro, 2020-b). What’s more, there is some research shows that higher levels of nitric oxide might actually block the coronavirus from replicating in the lungs and causing damage (Åkerström, 2005). Some healthcare providers have even explored the use of nitric oxide itself as a treatment for patients with severe COVID-19 (Bagate, 2020). 

While all of this research is interesting, none of these treatments have yet been approved for use. So if you have coronavirus and start experiencing breathing issues, please seek medical help right away instead of trying to treat it on your own (CDC, 2020-d).

What to do if you have coronavirus

If you’ve received a positive COVID test or suspect you have coronavirus, keep track of your symptoms. Most people can stay at home and self-isolate. Call your healthcare provider or head to an emergency room immediately if you experience: trouble breathing, persistent pressure in your chest, confusion, inability to stay awake, or bluish lips or face (CDC, 2020-d).

If you have coronavirus, it’s important that you quarantine at home until you’ve hit milestones that are considered safe. That includes after self-isolating for 10 days, going 24 hours without a fever without using fever-reducing drugs, and after your other symptoms have started improving (CDC, 2020-a).

If you take sildenafil for pulmonary arterial hypertension (PAH), continue to take your medication as prescribed—even if you have coronavirus. There’s no evidence that any prescription drugs make COVID symptoms worse. Not taking medication for a serious health condition can be dangerous. You should only make changes to your medication after talking to your healthcare provider (CDC, 2020-c).

References

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  2. Bagate, F., Tuffet, S., Masi, P. et al. (2020) Rescue therapy with inhaled nitric oxide and almitrine in COVID-19 patients with severe acute respiratory distress syndrome. Annals of Intensive Care 10, 151. Retrieved from https://annalsofintensivecare.springeropen.com/articles/10.1186/s13613-020-00769-2
  3. Centers for Disease Control and Prevention (CDC). (2020-a, December 1). When you can be around others after you had or likely had COVID-19. Retrieved Jan 08, 2021, from https://www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/end-home-isolation.html
  4. Centers for Disease Control and Prevention (CDC). (2020-b, December 29). Certain medical conditions and risk for severe COVID-19 illness. Retrieved Jan 10, 2021, from https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html#heart-conditions
  5. Centers for Disease Control and Prevention (CDC). (2020-c, December 31). Coronavirus (COVID-19) frequently asked questions. Retrieved Jan 08, 2021, from https://www.cdc.gov/coronavirus/2019-ncov/faq.html#:~:text=Currently%2C%20there%20is%20no,have%20questions%20or%20concerns.
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