There are often media reports of athletes misusing drugs in the pursuit to enhance their performance in sport. With the 2008 Beijing Olympics on the horizon, media coverage of such stories will be magnified.
Far from being a new phenomenon, anecdotal reports of performance enhancement date back to the ancient Olympic games in Greece where mushrooms were used in the belief that they delayed fatigue in endurance runners.
The responsibility of co-ordinating the fight against doping now lies with the World Anti-Doping Agency (WADA). The WADA produces a code for sports and anti-doping authorities to sign up to. A key principle of this code for athletes is the rule of strict liability.
This makes the athlete responsible for adhering to the rules of their sport and solely responsible for the presence of any prohibited substance found in their sample, whether intentional or not.
The WADA also produces a number of mandatory international standards, including the prohibited list, which is updated annually (see box, below).
|Categories of Prohibited Substances and Methods according to the 2008
Prohibited substances: (Prohibited in competition and out of
Prohibited substances: (Prohibited in competition)
|Prohibited substances in particular sports
See latest prohibited list for restrictions in your sport
Prohibited methods: (Prohibited in competition and out of competition)
M1: enhancement of oxygen transfer
M2: chemical and physical manipulation
M3: gene doping
Check the current prohibited list for those substances and methods
prohibited under the above categories - www.wada-ama.org
Substances or methods will be on the prohibited list if they meet two of the following three criteria:
- The substance or method has the potential to enhance, or does enhance performance
- The substance or method represents an actual or potential health risk to the athlete
- WADA's determination that use of the substance or method violates the spirit of sport.
In addition to the substances and methods, those in sport who supply or possess prohibited substances or who assist others with breaches of the regulations are also subject to major penalties.
One such network of doping that has resulted in athletes and those around them being penalised is the Bay Laboratory Corporation investigation taking place in the USA.
Many doctors may have been extremely surprised when Dwain Chambers recently gave evidence to UK Sport and listed a complex series of drugs taken to boost his performance.
He named seven substances of which six were prohibited, including tetrahydrogestrinone (a designer steroid), testosterone/epitesterone cream, erythropoietin, human growth hormone, insulin, modafinil and the non-prohibited thyroxine.
One commentator stated that to be a successful athlete you now need three things: a great coach, a great doctor and a great lawyer. We've reached the stage where any superlative athletic performance tends to be scrutinised closely and cynically.
For the remainder of this article the main categories of prohibited substances are summarised with a brief explanation of their impact in sport.
GPs will not need to know everything on the list but having a general understanding will help to support any patients who are athletes.
When drugs in sport are mentioned it is usually the androgenic anabolic steroids (AAS) that people think of. There is a much greater variety of prohibited substances and methods than just this group.
All of the AAS and similar related substances are prohibited. They have historically been abused in power disciplines such as weightlifting and sprinting, and as their name suggests promote anabolism and creation of large muscle bulk. Their use is not confined to body builders and power athletes; there is currently a vogue for image conscious young men and women to use them to create the 'perfect body'.
Few GPs will have prescribed a drug in this group but most will be aware of the potential side-effects, and athletes should be made aware of these.
Ben Johnson at the 1988 Seoul Olympics was one of the earliest big names to hit the media for misusing anabolic steroids when he returned a positive test for stanozolol.
Later confessions also showed he had used human growth hormone, which sits in the second class of prohibited substances, hormones and their related substances.
Peptide hormones such as insulin are also prohibited under this category and if prescribed medically require certification for appropriate medical use. Asthma treated with beta-2 agonists is another example of medication that requires special notification and the granting of what is known as a therapeutic use exemption.
The British cyclist Tommy Simpson died in the 1967 Tour de France and the post mortem showed high levels of stimulants, commonly used by athletes in the 1960s, in his system.
Increasing combative traits and reducing fatigue, stimulants can also be addictive and precipitate life-threatening dysrhythmias. Many stimulants including modafinil, ephedrine and methylphenidate are prohibited in sport. Caffeine was, even until a few years ago, prohibited in competition. This is no longer the case, but it is still closely monitored and should patterns of abuse be identified it may be reintroduced to the prohibited list.
Blood doping came to the fore in the 1984 Los Angeles Olympics. It was revealed after the games that members of the successful US cycling team had been transfused with packed red cells to increase their haemoglobin levels, oxygen transport and workload capacity. Now a prohibited method, Alexander Vinokourov in the 2007 Tour de France was caught having transfused someone else's blood into his system.
The availability of erythropoietin is another way of increasing red blood cells and endurance capacity but has also recently been shown to be a substance used by power and sprint athletes as part of their recovery from heavy sessions allowing them to undertake a harder training programme.
Analgesics and diuretics
Finally, potent analgesics like morphine are on the prohibited list although analgesics such as paracetamol are acceptable.
The beta-blockers are prohibited due to their value in sports where fine motor control is a factor. Diuretics are on the list because they are useful in sports having a weight limit for a particular category.
Several of the above examples demonstrate that routinely prescribed medicines are prohibited, and this can obviously be an area where an athlete may unintentionally make a mistake.
This is no excuse, and the UK Sport Drug Information Database site, is a dedicated resource where athletes and support staff can check the prohibited status of any licensed UK medication.
Next issue I shall discuss the process that athletes should go through to ensure their medical requirements do not prevent them competing in sport or, even worse, are the cause of an anti-doping rule violation.
Dr Jarvis is a GP in Boscastle, Cornwall, and a medical officer to the Commonwealth Games Council for England and to British Cycling
- Many thanks to Michael Stow and Nick Wojek at UK Sport for their helpful suggestions in the preparation of this article
- UK Sport Drug Information Database - www.didglobal.com.