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How chemo affects you and your bone marrow

Chemotherapy works to destroy fast-growing cells, like cancer cells. But there are other types of fast-growing cells in your body that could also be targeted by chemo—normal, healthy cells like those in your bone marrow.

Your bone marrow makes blood-forming cells, which are the parent cells that make red and white blood cells. Red and white blood cells help your body work properly and help protect you from the risk of infection. Chemo can damage those parent cells, which can reduce the amount of red and white blood cells in your body. This is called bone marrow suppression, or “myelosuppression.”

How blood cells help your body

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White blood cells help fight off infection and protect you from viruses and bacteria.

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Red blood cells pick up oxygen from your lungs and carry it to cells throughout your body.

Unfortunately, chemotherapy can't tell the difference between the normal, healthy cells and the harmful cancer cells. So while chemo works hard to destroy the cancer cells, it can also damage the important blood-forming cells, too.

Chemo can damage your normal, healthy cells

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Damage to blood-forming cells from chemo can make your white blood cell count drop too low. This is a side effect called neutropenia (noo-troh-PEE-nee-uh) and means you could be at risk for infection.

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Damage to blood-forming cells from chemo can also make your red blood cell count drop too low. This side effect is called anemia (uh-NEE-mee-uh) and can make you feel very tired, weak, dizzy, or make breathing more difficult.

Neutropenia and anemia can get serious

Both neutropenia and anemia due to chemo could become severe enough to require hospitalization or a blood transfusion. These side effects can also cause a delay in your cancer treatment or a drop in your chemo dose. Your doctor will monitor your blood counts on a regular basis to make sure they are at the right levels.

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Make sure to always tell your doctor or nurse about any symptoms you are having such as fever and fatigue.

COSELA™ (trilaciclib) can help protect the blood-forming cells and lower your risk of bone marrow suppression, a harmful side effect of chemo.

Learn more about how COSELA can help protect your bone marrow