D'Hooghe said the abuse of anti-inflammatories is increasingly more prominent among teenage players who counter any bruise or over-exertion of muscles with the strong medicines which can have serious effects on kidneys, stomach and intestines later in life.
"The most worrying aspect is that we see the problem moving ever more into the youth categories," D'Hooghe said in an interview with The Associated Press.
He said the increase among younger players was especially evident at the 2011 Under- 17 World Cup in Mexico and had risen since.
FIFA has been hit by relatively few major doping cases in its history and D'Hooghe said beyond the cost of the anti-doping testing program, the world football federation should try to centre on other issues, too.
"Doping is not our biggest problem. The anti-inflammatories are our biggest problem," D'Hooghe said.
FIFA got its first major warning on the abuse of the non-steroidal anti-inflammatory at the 2010 World Cup in South Africa, where teams have to let FIFA know from 72 hours in advance of a game what medicine players get.
"There was one team where 21 of 23 players were using them," D'Hooghe said.
The overall percentage stood at 34.6 per cent in South Africa, but that already was an increase compared to 29 per cent at the 2006 tournament in Germany.
D'Hooghe and FIFA's medical team have been looking at other tournaments since, and increasingly youth competitions.
"We can see it going crescendo," he said. "For the young, it used to be nil, but now we are starting to see it shape up as something serious."
As so often, the problem comes down to the same issue — too many games, week-in, week-out, for club and country. FIFA medical officials have indicated a maximum of matches should stand at 60 but many players go above that. Instead of natural rest to restore joints, tendons and muscles, anti-inflammatory drugs get players back in shape for the next match.
"The medicine gives you less pain, but you worsen the situation because pain is a warning. It is an alarm bell," D'Hooghe said. "At a certain point, some players start thinking they cannot play without taking the pills."
And that starts cascading from senior games to junior matches.
"They start taking the example from their elders," D'Hooghe said.
There is no fool-proof way to act against the abuse since the medicine is often available over the counter, and not on any banned anti-doping list.
Education is the only solution, D'Hooghe said. FIFA is organizing a major medical conference in Marrakesh, Morocco, next year where the 208 national federations will send their top medical officials for instructions.
"It will be a big theme there," D'Hooghe said.