How Medications Work Don't assume that extreme exhaustion, or the other symptoms listed above, are simply a part of having cancer. If your doctor determines that you have anemia, a drug to stimulate red blood cell production can be prescribed. These medications are synthetic forms of erythropoietin, the hormone in your body that stimulates red blood cell production. The medicine is given by injection and directs the bone marrow to churn out more red blood cells. More red blood cells means more hemoglobin and more oxygen reaching your cells. Soon, your anemia symptoms should subside, and you should feel much better.