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How Performance-enhancing Drugs Work


Masking Drug Use
Lyle Alzado of the Los Angeles Raiders looks on at a 1990 training camp in Oxnard, California. He died of brain cancer in 1992. Alzado believed - though it wasn't proven -- the cancer was caused by steroids and HGH, which he used for more than 20 years.
Lyle Alzado of the Los Angeles Raiders looks on at a 1990 training camp in Oxnard, California. He died of brain cancer in 1992. Alzado believed - though it wasn't proven -- the cancer was caused by steroids and HGH, which he used for more than 20 years.
George Rose/Getty Images

As previously mentioned, diuretics can be used to reduce the presence of drugs in urine samples. Other compounds, including epitestosterone, plasma expanders and secretion inhibitors, can be used to reduce the presence of banned substances in blood samples.

Epitestosterone

Epitestosterone is a biological form of testosterone that does not enhance performance. Drug tests for testosterone typically measure the ratio of testosterone to epitestosterone (T/E ratio). An athlete can inject epitestosterone, lower the T/E ratio and hide the use of testosterone. By itself, epitestosterone has no real harmful side effects.

Plasma Expanders

Plasma expanders are substances that are used to increase the fluid component of blood. They are used to treat victims of shock, trauma and surgery. Athletes can use these substances to dilute the concentration of banned substances (EPO) in their blood. Most side effects include moderate to severe allergic reactions.

Secretion Inhibitors

Many drugs and foreign substances have structures that are shaped like organic acids. In the body, these organic acids are removed by a protein in the kidney that transports organic acids. If this protein can be blocked, then these drugs or foreign substances would not appear in the urine. Doctors use these inhibitors to treat gout. However, the drugs can be used to manipulate the results of urine drug tests. Possible side effects include nausea, vomiting, allergic reactions and kidney problems.