Cytokine release syndrome (CRS) is a condition brought on by certain medications, treatments, and infections.

It happens when a large volume of proteins known ascytokinesare suddenly released into the body.

In some cases, cytokine release syndrome can be severe or even fatal.

Person resting in hospital

Boyloso / Getty Images

Boyloso / Getty Images

What Is a Cytokine?

Cytokines are tiny proteins that play an important role in the bodys immune response.

They tell the immune system how to fight off pathogens and illnesses, such as viruses and cancer.

Jurairat J. Molina, MD

Some laboratory-made cytokines are used to treat cancer and other serious conditions.

A Word From Verywell

Symptoms can range from mild flu-like symptoms to severe life-threatening symptoms.

Cytokine release syndrome is treatable.

Are There Different Stages of Cytokine Release Syndrome?

Symptoms may range from mild to serious or even life-threatening.

These are problems within the nervous system.

Common triggers for cytokine release syndrome are:

How Is Cytokine Release Syndrome Diagnosed?

Low-flow oxygen therapy may be helpful in relieving mild respiratory symptoms.

Some research also suggests prophylactic (preventive) treatment with Blincyto orsystemic corticosteroidsas a means of prevention.

If you are going to undergo immunotherapy, discuss your concerns about CRS.

Let your healthcare provider know about any other medications youre taking, as well as your medical history.

This often happens as a result of immunotherapy, although it can also occur due to infection.

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American Cancer Society.Cytokines and their side effects.

2021;10(21):5190. doi:10.3390/jcm10215190

National Cancer Institute.T cell.

Murthy H, Iqbal M, Chavez JC, Kharfan-Dabaja MA.Cytokine release syndrome: Current perspectives.Immunotargets Ther.

2022;30(5):1503-1516. doi:10.1007/s10787-022-01040-9