Trainer Mahmood Al Zarooni has been banned for eight years for his part in the Godolphin doping scandal.
The British Horseracing Authority banned 15 of the stable's horses for six months each earlier on Wednesday after they tested positive for anabolic steroids.
The BHA has now decided to revoke 37-year-old Al Zarooni's licence for eight years.
"Mahmood Al Zarooni has been disqualified for eight years by the disciplinary panel of the British Horseracing Authority after admitting administering anabolic steroids to horses in his care," read an official statement.
"The Godolphin trainer said he had made a 'catastrophic error' in using the banned drugs on a number of runners in his yard, including former Qipco 1,000 Guineas favourite Certify."
The maximum ban that could have been imposed on the trainer was 10 years.
