Mark Webber has renewed calls for Formula One drivers to be drug tested after fellow Australian Moto2 rider Anthony West was found guilty of using a prohibited substance.
The 31-year-old, who competes for the QMMF Racing Team in the feeder class to the MotoGP, tested positive for the stimulant Methylhexaneamine following his race at Le Mans on May 20.
West was on Thursday banned from the sport for one month.
The penalty came less than a week after the Australian finished second at his home round at Phillip Island.
Webber said he wasn't familiar with the substance West used, but said a lot of motorcycle riders compete under "pretty heavy pain killers" at times.
"Whether it was linked to that, I'm not sure," he said.
"Obviously it's good they're doing what they can to make sure everyone's as kosher as possible but I think it's quite difficult for that category, because you see these guys that are riding ... extremely injured."
Nevertheless, Webber said if West's drug taking was to do with performance enhancing, "he'll learn from that and move on."
The Red Bull driver, who goes into this weekend's Abu Dhabi Grand Prix in fourth place on the drivers' championship ladder, said F1's governing body should join its motorcycle counterparts and drug test competitors to provide "clarity".
"I've always been championing the idea to do more of it, but the FIA have never really been that strong on it," Webber said.
"The other drivers have never been super strong on it, so it's never really been a huge issue.
"You know, with what's at stake, the money involved and all that type of stuff, people do things.
"It's extremely unlikely but you never say never."
If West decides not to appeal his ban, he will be ruled out of the final round of the Moto2 series at Valencia on November 11.