• It has been hypothesized (suggested) by some experts that ACE inhibitors could make COVID-19 worse. But because COVID-19 is a new disease, we do not know if they actually do.
• ACE inhibitors reportedly increase levels of ACE-2 which is the protein that the SARs-CoV-2 virus binds to, and long-term use may also suppress the immune response.
• However, an overactive renin-angiotensin system may be another reason people with high blood pressure are more likely to develop pulmonary complications from COVID-19.
• There is currently no evidence that ACE inhibitors do make COVID-19 worse. But it is something that needs to be investigated further, to help guide practice during this current COVID-19 pandemic and for any new coronaviruses in the future that use ACE-2 as an entry point as well.
• Do not stop taking your ACE inhibitor because this may increase your chance of having a heart attack or stroke. If you have any concerns, talk to your doctor.

Why has concern been expressed with regards to ACE inhibitors?

Early on in this pandemic, researchers discovered that the SARS-CoV-2 virus, the virus that causes COVID-19, enters our body via ACE-2.

ACE-2 is a type of protein that is found in abundance throughout our body, particularly in the cells inside our mouth but also in our lungs, intestine, blood vessels, and kidneys. ACE-2 controls the production of ACE, an enzyme that is part of a wider system that has many vital roles in the body, such as regulating blood pressure.

Research has found that levels of ACE-2 are increased in people with high blood pressure and diabetes, and also by some drugs, such as ACE inhibitors or Angiotensin receptor Blockers (ARBs). Genes also control how much ACE-2 an individual has in his/her body, and their response to ACE inhibitors or ARBs.

But in order for the SARS-CoV-2 virus to bind to ACE-2, it first has to modify the surface of the protein in a process called glycosylation.

• Inhibiting ACE-2 glycosylation has shown to significantly reduce the infection of host cells by SARS-CoV-2 in a laboratory. This is the process by which chloroquine, hydroxychloroquine, and serine protease inhibitors are thought to work.
• It has been reported that long-term use of ACE inhibitors appears to modify how our immune system responds to viral infections, in a similar way that NSAIDs are reported to suppress our immune response.

Should I stop taking my ACE inhibitor?

No. Do not stop taking your ACE inhibitor without talking to your doctor first. ACE inhibitors are very effective at reducing high blood pressure, for heart failure, and for protecting the kidney in people with diabetes.

Stopping these drugs may result in a heart attack or stroke, which far outweighs the hypothesized chance of worse COVID-19 outcomes.

There may be other reasons people with heart disease or diabetes are more at risk of COVID-19 complications, such as an overactive renin-angiotensin system (the hormone system that regulates blood pressure).