Jockey Levi Williams has been banned for six months after testing positive for cocaine and cannabis.
Williams, 22, has sought help to stop his drug use since the failed test at Wolverhampton races on 29 January, a disciplinary hearing was told.
He had been placed on furlough during the Covid-19 pandemic and admitted making a “stupid mistake”.
The rider has offered to use his experiences to teach young jockeys about the danger of using drugs.
“He is very happy to assist in speaking to new entrants about the real damage and career risk drug use represents,” said Rory MacNeice, representing Williams.
“He has changed his living arrangements and is now in a much more supportive environment.
“He recognises his experience may help others from making the same mistakes.”
Last month British horse racing started a two-month pilot of using saliva tests to screen jockeys for cocaine and other banned substances.
There has been an increase in the number of positive urine samples in recent years, with six in 2019 and five in 2020, after no more than three positives in a single year between 2012 and 2018.
Jockeys Adrian McCarthy and Finley Marsh were both given six-month bans in March for using cocaine.
In April, jockey Benoit de la Sayette failed a drugs test days after denying taking cocaine.
Andrew Howell, for the British Horseracing Authority (BHA), said Williams admitted breaching the rules.
The jockey said he had only smoked cannabis once or twice, including when at a party with friends around New Year. “I didn’t really think, I was just stupid,” he said.
He also used cocaine when he was not riding, but realised it was “a bad idea” and has since sought help from the Sporting Chance charity and the Professional Jockeys’ Association.
“This is an important and encouraging step from the BHA’s perspective,” said Howell.
Brian Barker, chairman of the disciplinary panel, said: “You have made real efforts to rehabilitate yourself and put your knowledge to good use to help others.”
Williams will be eligible to reapply for his licence from 4 August after serving an interim suspension since 5 February.
His last winner came on Lethal Talent, for Newmarket trainer Jane Chapple-Hyam, at Lingfield on 31 December, 2020.