What is myelosuppression? What causes it? What are the signs and symptoms? And how should it be monitored and treated? Myelosuppression is when the bone marrow is suppressed by either drugs or sometimes infection. It speaks to blood counts being low. So maybe your white blood cells, red blood cells or platelets. It should be managed by being monitored and depending on what's the cause of the myelosuppression dictates what the monitoring should be. Generally post-transplant the myelosuppression is monitored with basic lab work every couple of days or even every day and then transfusions of red blood cells or platelets could be given for support through that period of time and GCSF or white blood cell growth factor can be given for support of low white blood cells.