Australia's first heavyweight boxing world champion, Lucas Browne, has been officially stripped of his World Boxing Association (WBA) title after his 'B' sample also tested positive to an illicit substance.

Browne tested positive to banned weight-reducing drug clenbuterol in a test conducted by Las Vegas agency Voluntary Anti-Doping Association (VADA) on the day of his WBA bout with Russia's Ruslan Chagaev in Chechnya.

No immediate action was taken until the 'B' sample was tested, ultimately confirming the results of the 'A' sample test.

As a result, Browne has been stripped of his title and suspended for six months.

What is clenbuterol? Not approved for human use in Australia

Not approved for human use in Australia Used for anabolic (muscle growth) and catabolic (fat reduction) benefits

Used for anabolic (muscle growth) and catabolic (fat reduction) benefits Used to treat asthma by relaxing muscles in the airways - often used in veterinary medicine

Used to treat asthma by relaxing muscles in the airways - often used in veterinary medicine On WADA and ASADA's prohibited lists

On WADA and ASADA's prohibited lists Dangers include heart palpitations, headaches, high blood pressure, nausea, cramps and tremors

Dangers include heart palpitations, headaches, high blood pressure, nausea, cramps and tremors Risk of stroke when used in high doses

Risk of stroke when used in high doses Alberto Contador stripped of 2010 Tour de France title for clenbuterol use Source: National Drug Strategy

According to the WBA, Browne, who has always claimed he did not knowingly ingest clenbuterol, questioned why a heavyweight would use a weight-reduction drug.

He also maintained his stance that it must have been in something he ate, having earlier said a test six days before the March 5 fight came back clean.

"Following that clean test I ate only at the hotel in which we were hosted and at the meal following the boxers' media weigh in," he said.

"The water I drank on the night of the fight was sealed bottled water."

Even so, the WBA said "there is no way to determine if that is true or not" and the association has repeatedly said the boxer and his team are responsible for what enters his system.