Doctor Decoded: What's a Cytokine Storm?

“Cytokine storm” is a phrase that seems to have come out of nowhere — much like the COVID-19 pandemic itself. By now, you’ve likely heard this phrase on the news as doctors warn of COVID-19 complications. But what is a cytokine storm? Furthermore, what is a cytokine?

Cytokines, decoded

Cytokines are proteins that act as immune system messengers. They can either speed up or slow down the immune response. When a pathogen or other threat invades the body, the immune system releases these cytokines. This helps your body fight off the threat, whether it’s food poisoning or COVID-19.

In other words, cytokines can often be a good thing. In fact, cytokine therapy is a type of immunotherapy to treat certain types of cancers, including metastatic melanoma and metastatic kidney cancer.

Cytokine storm, decoded

The problem with cytokines is if the body releases too many at once. This is called a cytokine storm. When this occurs, the cytokines overstimulate the immune system, which may lead to organ damage or even organ failure.

COVID-19 brought awareness to cytokine storm recently, but they're not unique to the coronavirus. In fact, they can happen as a result of any infection. They may also stem from some diseases, like autoimmune conditions, or in response to certain treatments.

Symptoms of cytokine storm include high fever, redness, swelling, inflammation, nausea, and blood clots (which could increase the risk of stroke or heart attack). A cytokine storm can be a life-threatening situation, so it’s one of the ways in which COVID-19 can be fatal.

The best way to prevent a cytokine storm related to COVID-19 is to prevent the coronavirus infection altogether. Here are tips to reduce the spread of COVID-19.