By Don H. Catlin, MD

The use of performance-enhancing drugs (PEDs) by athletes in sport competitions is a major public health issue the world over. It not only jeopardizes the health of athletes, but also threatens the health of children who view athletes as role models and imitate their behavior.

As one report put it, "Doping perverts the meaning and core values of sport, undermines the legitimacy of competition, and sends messages to our children that winning at any cost is the highest value."

Athletes who take drugs gain an unfair advantage over those who don't, destroying the notion of a level playing field. Spectators like to know that all athletes are drug-free and not risking serious harm or death by using potentially dangerous training methods.

The past 50 years have seen so many scandals involving athletes taking PEDs that it can no longer be assumed that they will normally compete drug-free. That is why testing is necessary.

Evolution of PED Testing

That some athletes will use PEDs, coupled with advances in analytical chemistry, has led sport officials to sanction urine testing for PEDs and to ban from competition athletes who test positive. In the 1960s, it was generally believed that only certain stimulants—primarily amphetamines, cocaine, and strychnine—were used to enhance performance. Such drugs are taken at the time of competition to gain a competitive edge. The first doping control tests were therefore developed and administered at the time of competition to curtail the use of stimulants.

By the 1970s, however, it was apparent that any drug that could enhance performance—most notably, anabolic androgenic steroids—would be used by elite athletes who had access to them. Whereas stimulants act immediately, the effects of steroids are gradual. Steroid users bulked up during training and discontinued drug use in advance of competition. As a result, in 1991, the first "out-of-competition" drug tests were developed. Today, unannounced out-of-competition testing is considered indispensable to antidoping programs.

Infrastructure for PED Testing

By 1960, doping was becoming a serious problem. At the behest of the International Olympic Committee (IOC), a medical commission was developed to deal with the issue. The result was a medical code that spelled out that doping was forbidden, specified sanctions for athletes who tested positive, detailed the development and accreditation of IOC laboratories to conduct PED testing, and prepared a list of banned substances. However, testing was time-consuming and expensive, and it was distracting the IOC from its primary mission: organizing and running the Olympic Games.

In 1999, the IOC proposed the World Anti-Doping Agency (WADA), whose function would be to take over drug testing. Today, 35 accredited WADA laboratories around the world are now available to any sport organization, not just the Olympics, to test for banned drugs in competing athletes.

Drug-Testing Tools

Gas chromatography (GC) or liquid chromatography, in combination with mass spectrometry (MS), is used to detect most banned substances. Chromatography is a technique that separates the components of a chemical mixture by passing them over a stationary solid- or liquid-adsorbing medium.

An athlete's urine is prepared for GC/MS by various chemical steps. When GC is used, for example, a tiny portion of the urine mixture (2 µL), which may contain banned drugs, is injected onto the head of a narrow, 50-meter-long glass column inside an oven that is heated at high temperature. The sample is immediately volatized (ie, evaporated) and is swept down the column by inert gases. This process is timed; components of the mixture are retained by the column at different retention times. Different drugs are known to have specific retention times.

The drugs form isolated bands that can be observed on a computer printout. The peaks or bands on the printout are then analyzed, which produces a spectrum. The mass spectrum of each substance is unique. If the mass spectrum and the retention time at which it was detected are identical to that of a drug standard, the substance has been identified. Most banned drugs are detectable by this method.

Drug-Testing Protocols

Urine is collected from athletes under observation at the site of the competition. Once urine is collected, it is split into two bottles labeled A and B. Both samples are sent to a WADA-accredited laboratory.

If the A sample of an Olympic athlete contains a banned drug, the head of mission of the athlete's country of origin is informed and he/she informs the athlete. The next day, the athlete comes to the laboratory and observes while the analysis is repeated. In all recent Olympic Games, an A sample that has tested positive has always been confirmed by finding the same drug in the B sample.

Finally, the IOC reviews the situation. If the committee agrees that the analysis confirms the use of a banned drug, the athlete is sent home on the next available flight.

Anabolic Steroids

The misuse of anabolic steroids for improving sport performance dates to the 1950s, when a US physician observed that Soviet weightlifters at a powerlifting championship were using testosterone. By the 1980s, steroids were being used by athletes in many sports. For many of these years, it was not clear whether the large muscles induced by anabolic steroids were strong muscles. In 1996, however, persons receiving 600 mg of testosterone enanthate per week for 10 weeks showed increases in muscle strength and size.[2]

Anabolic steroids do not enhance performance in the short term. They are taken months before the event, and if testing is anticipated, they are discontinued 3-4 weeks before the scheduled test.

Anabolic steroids used by athletes are synthetic derivatives of the male sex hormone testosterone. They act by binding to specific receptors inside a cell to enhance or inhibit the expression of specific genes. The androgenic effects include increased body hair, oily skin, acne, hypertension, and changes in cholesterol. In women, breast atrophy, amenorrhea, increased facial hair, and male-pattern baldness may occur.

Testing for Anabolic Steroids

Urine testing for anabolic steroids formally began with the 1976 Olympic Games and has increased in sophistication and frequency ever since. The classic detection method is GC/MS, which detects steroids in urine. More sensitive high-resolution MS can now detect steroids at much lower concentrations. The problem is distinguishing normal testosterone (T) in the urine from that administered by injection, patch, cream, or gel.

Most people produce in their urine one molecule of T for every molecule of the related steroid epitestosterone (E), resulting in an average T/E ratio of approximately 1:1 in males and females. An elevated T/E ratio that distinguishes natural from self-administered testosterone—usually, 6:1 or greater—is used as a marker of abuse. However, this approach is imperfect: Some people normally have a T/E ratio greater than 6:1, and some self-administering steroid users manage to keep their T/E ratio below this value. Recently, sport authorities have imposed random-selection year-round testing schedules on short notice (up to 48 hours). Over 40 anabolic steroids have been marketed worldwide.

Amphetamines

Stimulant use to enhance performance dates to the first Olympics and even earlier. Amphetamines, the most common class of stimulants used by athletes to gain a competitive edge today, elevate blood pressure and initially slow the heart rate. Amphetamines are popular owing to their ability to delay fatigue onset during intense exercise; reduce body weight; and increase speed, power, endurance, concentration, and fine motor coordination, thus enhancing performance.

Potential adverse effects include restlessness, irritability, insomnia, headache, palpitations, anorexia, irregular heartbeat, confusion, hallucinations, convulsions, cerebral hemorrhage, heart attack, and circulatory collapse. Stimulants on the WADA banned drug list include amphetamine, ephedrine, cathinone, strychnine, phentermine, and many others.

Testing for Amphetamines

Amphetamines are "time-of-event" drugs, used at the time of competition rather than during training. The period of detection in urine by GC/MS is up to 5 days after last use. Amphetamines are absorbed rapidly into the circulation, with blood levels peaking in 1-2 hours. Clinical effects can appear within 30 minutes and can last over 3 hours.

Amphetamines are readily detectable in urine, but testing is complicated by their similarity to sympathomimetic amines, which are widely available as over-the-counter cold remedies. Sympathomimetic amines are also used to treat seasonal allergies, related respiratory disorders, and asthma. Testing for different forms of amphetamine and methamphetamine ensures the accuracy of the testing results and guarantees that there are no false-positives.

Human Growth Hormone

Human growth hormone (hGH) is a peptide hormone secreted by the pituitary gland. A major function is to maintain normal growth rates from birth until adult height is attained. hGH appeals to athletes who are trying to increase lean body mass and shorten recovery time. Although muscle size may increase, there is no evidence of increased muscle strength.

Many athletes think that hGH use will give them the same effects as anabolic steroids, without the risk for the drug being detected or the same adverse side effects. But hGH has its own side effects, including headache; enlargement of the adenoids; further growth of the hands, feet, and face; enlargement of the heart, liver, spleen, and kidneys; disorders of the peripheral nerves; diabetes; hypertension; premature cardiovascular disease; impotence; osteoporosis; and colonic polyps.

Testing for hGH

Two different serum-based tests may be used to detect the use of pharmaceutical hGH, referred to as "recombinant hGH" (synthetic hGH is manufactured from recombinant DNA). One, the isoform test, was introduced in 2006; the other, the biomarker test, is still in development.

Doping with recombinant hGH alters the naturally constant proportions between the different isoforms (ie, types) of hGH present in blood of an individual. The isoform test was developed to detect the changes in the proportions of different hGH isoforms after use of recombinant hGH. The biomarker test looks for telltale increases in blood markers in the liver and collagen that appear after hGH injection.

The two tests are complementary. The isoform test detects alterations in the proportions between hGH isoforms up to 24-48 hours after recombinant hGH administration. The biomarker test may not detect the initial phase of recombinant hGH use, but it can detect such use up to 1 month before testing.

Erythropoietin

Erythropoietin (EPO), a hormone secreted by the kidneys, partially controls the rate of production of red blood cells, which transport oxygen from the lungs to all parts of the body, including the muscles. The duration of peak benefits depends on how EPO is administered: 4-5 hours when administered intravenously, 5-24 hours when administered subcutaneously. Red cell production is stimulated for as long as 3 weeks.

EPO is used by athletes in aerobic sports as an alternative to blood doping. Blood doping and EPO administration both result in enhanced aerobic power. EPO can raise the red blood cell count and thickness of the blood, possibly resulting in clots, stroke, and heart attack.

Testing for EPO

Athletes who intend to dope carefully follow developments in the pharmaceutical industry. Even before synthetic EPO (Epogen®) was marketed in 1987, there were rumors of its use by athletes preparing for the Calgary Winter Olympic Games of 1988. The 1990s are referred to as the "years of EPO use" because there was no test, and several peer-reviewed journals had demonstrated efficacy. On the eve of the 1998 Tour de France, the trunk of a car filled with vials of EPO and related products was found by authorities. Many cyclists subsequently confessed to their plan to use the drugs during the Tour.

At about that time, several laboratories were working on ways to detect EPO. In 2000, a urine test that can detect differences between normal and synthetic EPO finally was presented by the French WADA-accredited laboratory. The method was complicated, took 2-3 days to complete, and had minimal retrospectivity; however, it was useful and enabled WADA labs to test for EPO for the first time.

Blood Doping

Blood doping is a banned method of improving athletic performance by artificially increasing the amount of hemoglobin in the bloodstream, allowing higher amounts of oxygen to reach the muscles; this can improve stamina and performance, especially in aerobic events, such as running and cycling. Blood transfusions, injections of EPO, and injections of synthetic oxygen carriers (eg, solutions based on recombinant, bovine, or human hemoglobin) are the most common methods of blood doping.

Blood typing and cross-matching and flow cytometry have been used to detect blood doping. However, there have been very few positive tests at the time of the Olympics. One athlete in the 1984 Summer Olympic Games in Los Angeles had his blood drawn and saved a few weeks before the Games. After the cells were reinfused some weeks later, he performed his personal best. Although several other participants in the Los Angeles Games also did this, there was no evidence that their performance was improved.

Dietary Supplements

Dietary supplements are readily available without prescription from Internet sources, convenience stores, and drug stores. Some 10,000 dietary supplements have been described. The vast majority of athletes consume supplements even though they may have no efficacy or contain banned substances.

One way athletes can avoid supplements that have been spiked with drugs on the WADA banned list is to use only supplements marked "doping-free"; these have been tested and found to contain no banned substances. Although there are no tests for the supplements themselves, if a supplement has been altered to contain banned substances, the athlete taking it will test positive. A list of high-risk supplements is available from WADA online.

Designer Drugs

A "designer" drug is one that is not known to be in use in the doping community and is not available unless a chemist is found who is able to synthesize it. The athlete who has taken a designer anabolic steroid is at an advantage in that he or she alone has this knowledge, and the drug is often undetectable by existing tests.

In 2002, our lab found a designer anabolic steroid—norbolethone (Genabol), still in development—in the urine of an athlete who had access to steroids. Norbolethone was discontinued because it proved too toxic for patients.

In 2003, a true designer anabolic steroid was discovered when our lab was provided with a suspicious syringe that contained a tiny drop of unknown fluid. After several weeks of complicated analytical work, tetrahydrogestrinone (dubbed "the clear")—the most powerful anabolic steroid ever tested—was found in the drop. Over the next few weeks, tetrahydrogestrinone was discovered in the urine of several high-profile athletes. It then disappeared.

Once a designer anabolic steroid is found and added to a lab's detection method, athletes tend to quickly find out about it, and it loses its designer (undetectable) status.

Therapeutic Use Exemptions

What if an athlete takes a drug on WADA's prohibited list that is prescribed by a physician for legitimate medical reasons? WADA's list of banned drugs is extensive. It includes not only the PEDs discussed in this slideshow, but also beta-2 agonists, diuretics, glucocorticosteroids, beta-blockers, narcotics, cannabinoids, and alcohol, among many others.

Although the list was developed to prevent athletes from taking PEDs and protect their health, it was not meant to prevent doctors from prescribing the correct medical treatment to their athlete patients. WADA has therefore developed criteria that must be met to grant a therapeutic use exemption: The athlete would experience significant health problems without taking the prohibited substance or method; the therapeutic use of the substance would not produce significant enhancement of performance; and no reasonable therapeutic alternative to the use of the otherwise prohibited substance or method is available. Examples include oral corticosteroids for inflammatory bowel disease and severe asthma, diuretics for cardiovascular and renal conditions, and insulin for type 1 diabetes.

The Future of Testing for PEDs

The use of PEDs is as old as sport. As soon as a test is developed to indicate the use of one banned drug, a new, undetectable drug is designed to replace it, and some athletes will take it. If PEDs are ineradicable, shouldn't they be legalized?

Whether the political will exists to ban drug-taking athletes from competition is also in question. Just before the 2016 Rio Olympics, in the most recent incident, it was revealed that Russia had a secret, systematic state doping program for its athletes extending back to the 2014 Sochi Olympics and beyond; evidence of this was mishandled by WADA officials, and IOC officials refused to act definitively on it. As a result, many Russian athletes were allowed to compete in the Rio Games under a cloud of suspicion. Even so, to discontinue testing would be a form of coercion. PEDs work, so all athletes would be forced to take them if they wanted to be competitive.

After running a testing lab for 25 years, I think we need different testing model. Maybe athletes should be divided into two groups: those who are willing to submit to drug testing and those who opt out. At least we would know who's who. Perhaps there should be different rules for athletes in each group, but clearly the model currently in use isn't working.