Erythropoietin (EPO) and Blood Doping FAQ
A. What is it blood doping and Erythropoietin?
Erythropoietin is a man-made version of the hormone in the human body that stimulates the production of red blood cells. (Erythropoietin is a naturally occurring hormone, produced by the kidneys, which stimulates the body to produce more red blood cells) When administered to a human it stimulates greater RBC production. It was developed for treating the reduction in red blood cells (RBC) that comes with kidney disease, HIV, cancer and those undergoing surgery. The use of EPO was classified as banned by the International Olympic Committee in 1990.
Blood doping is a method of infusing extra red blood cells either from a donor or from one's own red blood cells that were previously removed.
B. How does blood doping Erythropoietin work?
The increase in red blood cells causes an increase in the number of hemoglobin molecules per unit blood. Hemoglobin is the primary molecule that carries oxygen in the blood. More oxygen in the blood allows more oxygen to be delivered to the exercising muscles. Studies have shown that blocking hemoglobin causes a reduction in exercise performance, or adding hemoglobin causes a clear increase in exercise performance.
C. How is blood doping and Erythropoietin commonly used?
Typically, blood doping involves removing 2 to 4 units (900-1800ml) of blood from an individual. The RBCs are spun and separated from plasma, then stored in glycerol. After a 2-3 month time delay, which allows for restoration of RBC in the athlete, and about 3-5 days before competition, the RBC are "washed" and reinfused. Because of the storage in glycerol, the RBC are well preserved. Donor blood can be used, but risk is increased due to the possibility of blood borne pathogens. The benefit of donor blood is that the individual does not have to go through the period of regeneration of their own RBCs.
EPO is taken by IV or subcutaneous injection. For medical use the typical dosage is: Initial dosage-100IU/kg body weight 3 times/week for 8 weeks. The maintenance dosage is then 25-50IU/kg 3 times/week. The exact dosage is disease/individual dependent. For sport use, the dosage is usually 20-40IU/kg 3 times/week with no "loading" phase.
D. What are the side effects of blood doping and Erythropoietin?
There appears to be minimal side effects associated with blood doping, including no problems in research. Less is known about illicit use. There no changes in BP, which was suspected because of inferred increase in viscosity that was presumed to occur with blood doping. Donor infusion has obvious potential problems, and blood doping could be detrimental if too much is reinfused.
With EPO use the most common side effect appears to be an increase in blood pressure. This increase is not explained by increased hematocrit and presumed viscosity, but may be direct effect of the hormone on blood vessels, causing constriction. This constriction could possibly have very serious side effects, including death. It has been suggested that between 1987 and 1990, 19 Dutch and Belgian cyclists died from suspected misuse of EPO.