Low blood count due to chemotherapy

Low blood count due to chemotherapy

Blood cells are the normal cells most often affected by chemotherapy. A low blood count means having fewer new cells in the blood than is normal.

Key points to remember

This page is part of a whole section about childhood cancer.

  • a low blood count means having fewer new cells in the blood than is normal
  • blood cells are the normal cells most often affected by chemotherapy
  • there are 3 main types of blood cells -red cells, white cells and platelets

How does chemotherapy affect blood cells?

A low blood count means having fewer new cells in the blood than is normal.

Blood cells are the normal cells most often affected by chemotherapy. Blood cells form in the bone marrow which is a spongy material that fills the centre of long bones and flat bones. Some chemotherapy medicines slow down blood cell production. This halting of blood cell and platelet production in bone marrow is called myelosuppression.

What are the different types of blood cells?

There are 3 main types of blood cells:

  • red cells
  • white cells
  • platelets

How long does a low blood count last?

A drop in the blood cell count usually happens 7 to 10 days after your child starts receiving chemotherapy medicines. It takes about 3 to 4 weeks for the bone marrow to recover after the chemotherapy finishes and for the blood count to return to a near normal level.

How often will my child need blood tests?

Your child will have blood tests during chemotherapy to monitor the count levels of the cells. Your child will have blood tests as often as necessary to keep a close check on their blood count. Your child's healthcare team will monitor the results to see whether your child needs any supportive treatment.

The frequency of blood tests can vary from several times a day to several times a week.

For more information about low blood count see:

All the pages in the childhood cancer section of this website have been written by health professionals who work in the field of paediatric oncology. They have been reviewed by the members of the National Child Cancer Network (NZ). Medical information is authorised by the National Child Cancer Network Clinical Leader.

This page last reviewed 24 May 2018.
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