One of the effects of chemotherapy is a reduction in the total leukocyte count, which reaches its nadir around 10-12 days after the last course and then picks up again. In case of persistently low counts, your doctor may like to give G-CSF or GM-CSF to boost the marrow. There is no natural way to increase the TLC, except the use of the above mentioned immunoprotective drugs. These drugs stimulate the production of T-lymphocytes, macrophages, and other immune cells that are valuable in preventing the toxic effects on the bone marrow during chemotherapy. They also enable chemotherapy to be given at a higher dose that may make it more effective. In addition, colony growth factors are able to accelerate the regeneration of blood cells following chemotherapy. Current clinical experience with GM-CSF and G-CSF has shown that severe neutropenia due to chemotherapy may be prevented or at least decelerated, thus reducing the episodes of severe infections.