US Olympic and world 400 metres champion LaShawn Merritt has been suspended through July 2011 after testing positive for a banned substance found in a male enhancement product, the US Anti-Doping Agency (USADA) said on Monday.
The Beijing Olympic and 2009 world gold medallist had three samples test positive for prohibited testosterone prohormones, the anti-doping agency said in a statement.
He was suspended for 21 months, beginning October 28, 2009, the date of his first sample.
Merritt had accepted a provisional suspension in April "as a result of positive drug tests caused by his use of an over-the-counter male enhancement product," the American's attorney, Howard Jacobs, said in a statement at the time.
The statement said Merritt had used the over-the-counter product, which contained DHEA and pregnenolone, following the 2009 season.
Merritt acknowledged again on Monday he had made a mistake and said he was appreciative the three-member arbitration panel "agreed that I have never taken any substance to gain an advantage on the track," he said in a statement.
"I look forward to returning to competition as soon as possible and proving that my prior successes, including at the Olympic Games, were achieved honestly and fairly," he added.
