Dr Peter Larkins has explained why cannabis is considered performance-enhancing, following news West Coast’s Willie Rioli returned a positive reading to a metabolite of cannabis.

(He’s also explained what a metabolite is, too).

Rioli’s promising career has been thrown into chaos this month, with the young Eagle facing two ASADA investigations.

Many have questioned why Rioli is in trouble with ASADA, rather than the illicit drug code, following his match-day test to cannabis.

But Doc Larkins said there was a reason why marijuana fell under the ASADA code.

“It has different effects on different people, but generally it’s a calming agent to settle people’s nerves or anxiety,” he said on 3AW Mornings.

“So you can imagine in a sporting contest that can be useful for people.”

Doc Larkins also explained what a “metabolite of cannabis” meant.

“Often they (testers) are picking up the processed drug, not the drug itself,” he said.

“So when somebody has a positive test, it may not be the drug itself they’re detecting – it’s the by-product as it is being processed through the body’s excretion system.”

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