Chemotherapy can reduce the number of blood cells available to fight infection, carry oxygen, or help blood clot. These cells turn over rapidly in the blood stream and must be replaced by the bone marrow. Chemo can suppress blood cell production in the bone marrow which leads to low blood counts (myelosuppression).
Before each chemotherapy treatment, a sample of blood is drawn to determine whether blood counts are normal. If they are low, chemo may be postponed or the dose reduced. In some situations, medication is given to raise counts or a blood transfusion may be required. Chemotherapy can affect:
- Red blood cells: anemia.
- Platelets: thrombocytopenia.
- White blood cells: neutropenia.