British sprinter Nigel Levine has been given a four-year suspension from all sport for a doping violation, UK Athletics have confirmed.
Levine, a key member of Team GB's 4x400 relay team for more than a decade, has been punished after testing positive for prohibited anabolic agent clenbuterol in an out-of-competition test on 24 November 2017.
He was provisionally suspended by UK Athletics after being charged with breaching Article 2.1 of the Anti-Doping Rules, which relate to "presence of a prohibited substance or its metabolites or markers in an athlete's sample".
In a statement announcing the decision, UKAD chief executive Nicole Sapstead said: “All athletes must adhere to the principle of strict liability, and are solely responsible for any substances found in their system.
“Mr Levine is an elite athlete, who has competed at the Olympic Games, European and World Championships, and has received significant anti-doping education throughout his career.
“It is up to role models such as Mr Levine to uphold the highest standards when it comes to anti-doping, ensuring they check all supplements thoroughly and are 100 per cent certain they know that what they are consuming is not prohibited.”
Levine will now be banned from all sport from the date of his provisional suspension, 13 December 2017, until 12 December 2021 - when he will be 32.
Born in Trinidad and Tobago, Levine has won nine world and European Championship medals for Great Britain and had been hoping to make a comeback after a motorcycle accident last year that left him with career-threatening injuries, including a fractured pelvis.
Clenbuterol is used to help asthma sufferers, but is included on the banned list because it also helps improve athletic performance by burning fat and building muscle. Spanish cyclist Alberto Contador was banned for two years after testing positive for the substance at the 2010 Tour de France.