Dr Jirí Dvorák (pictured above) discovered that almost 40 per cent of players at the 2010 World Cup finals were taking some kind of pain-relieving medication prior to every game.

With the 2012 European Championship about to get under way in Poland and Ukraine, Dvorák has urged team doctors to think twice before giving players potentially "dangerous" pain killing and non-steroidal anti-inflammatory drugs (NSAIDs).

"Unfortunately, there is the trend to increase the intake of medication," Dvorák said.

"It is something that we have to really take seriously and ask what is behind it."

He believes that pressure on team doctors to get injured players on the pitch is partially to blame.

"The team doctors, most of them they are under pressure between the diagnosis and the appropriate treatment between the pressure to bring the player on the pitch, if they take them too long out they might be out of a job," Dvorák explained.

"Since 1998 we've collected data about the intake of medication for all players at every FIFA tournament, which roughly equates to 55 competitions from under-17 tournaments to senior club and national team competitions.

"The results are striking.

"Even at under-17 level, between 20 and 25 per cent of players are taking anti-inflammatory drugs and painkillers and this increases to senior World Cup levels, which sees 30 and 35 per cent of usage.

"When we combine that with the usage of non steroidal anti-inflammatory drugs, it equates to about half of the players."

Warning of potential consequences, Dvorák told fifa.com: "Some of the players are probably taking this medication without a prescription from the team doctors; they're just taking them and then telling the doctor.

"Others are taking them under prescription from the doctors as they're suffering some kind of pain or discomfort.

"But other players could also be using these painkillers in advance to reduce the pain caused by potential discomfort during a match.

"That could be dangerous.

"By masking symptoms through painkillers, you could be covering something which could be important in the long run.

"We need to raise awareness with the physicians responsible for the teams in all member associations so they think twice before prescribing this type of medication.

"Every medication you take has potential side effects, such as the building of blood content, but it could also have a negative effect on the function of the liver and kidneys, particularly if a particular medication has been taken for a long time."

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